psephology (n.) Look up psephology at Dictionary.com
"study of elections," 1952, from Greek psephizein "to vote" (properly "to vote with pebbles," from psephos "pebble") + -logy.
psephomancy (n.) Look up psephomancy at Dictionary.com
"divination by pebbles drawn from a heap," 1727, from Greek psephos "pebble" + -mancy.
pseudepigraphy (n.) Look up pseudepigraphy at Dictionary.com
"ascription of false authorship to a book," 1842, probably via German or French, from pseudo- + epigraph + -y (1). Related: Pseudepigrapha; pseudepigraphic (1830); pseudepigraphical (1838); pseudepigraphal (1630s).
pseudo (n.) Look up pseudo at Dictionary.com
late 14c., "false or spurious thing;" see pseudo-. As an adjective in this sense from mid-15c. In modern use, of persons, "pretentious, insincere," from 1945; as a noun from 1959. Related: Pseudish.
pseudo- Look up pseudo- at Dictionary.com
often before vowels pseud-, word-forming element meaning "false; feigned; erroneous; in appearance only; resembling," from Greek pseudo-, comb. form of pseudes "false, lying; falsely; deceived," or pseudos "falsehood, untruth, a lie," both from pseudein "to deceive, cheat by lies."

Productive in compound formation in ancient Greek (such as pseudodidaskalos "false teacher," pseudokyon "a sham cynic," pseudologia "a false speech," pseudoparthenos "pretended virgin"), it began to be used with native words in Middle English.
pseudo-science (n.) Look up pseudo-science at Dictionary.com
also pseudoscience, "a pretended or mistaken science," 1796 (the earliest reference is to alchemy), from pseudo- + science.
The term pseudo-science is hybrid, and therefore objectionable. Pseudognosy would be better etymology, but the unlearned might be apt to association with it the idea of a dog's nose, and thus, instead of taking "the eel of science by the tail," take the cur of science by the snout; so that all things considered we had better adopt the current term pseudo-sciences ["The Pseudo-Sciences," in "The St. James Magazine," January 1842]
pseudo-scientific (adj.) Look up pseudo-scientific at Dictionary.com
also pseudoscientific, 1816; see pseudo- + scientific; also compare pseudo-science.
pseudocide (n.) Look up pseudocide at Dictionary.com
"pretended suicide attempt," 1959, from pseudo- + ending abstracted from suicide.
pseudograph (n.) Look up pseudograph at Dictionary.com
"writing falsely ascribed to someone," 1828 (in German from 1809), from Late Latin pseudographus, from Greek pseudographos "writer of falsehoods," from pseudo- (see pseudo-) + graphos "(something) drawn or written" (see -graphy). Pseudography was in English from 1570s with a sense "misspelling."
pseudomorph (n.) Look up pseudomorph at Dictionary.com
"irregular form," 1838, earlier in German and French, from pseudo- + Greek morphe "form" (see Morpheus). Related: Pseudomorphic.
pseudonym (n.) Look up pseudonym at Dictionary.com
1828, in part a back-formation from pseudonymous, in part from German pseudonym and French pseudonyme (adj.), from Greek pseudonymos "having a false name, under a false name," from pseudes "false" (see pseudo-) + onyma, Aeolic dialectal variant of onoma "name" (see name (n.)).

"Possibly a dictionary word" at first [Barnhart]. Fowler calls it "a queer out-of-the-way term for an everyday thing." Properly in reference to made-up names; the name of an actual author or person of reputation affixed to a work he or she did not write is an allonym. An author's actual name affixed to his or her own work is an autonym (1867).
pseudonymous (adj.) Look up pseudonymous at Dictionary.com
1766, from Modern Latin pseudonymus, from Greek pseudonymos (see pseudonym). Related: Pseudonymously.
pseudopod (n.) Look up pseudopod at Dictionary.com
1862, from Modern Latin pseudopodium (itself in English from 1854), from Latinized form of Greek pseudo- (see pseudo-) + podion, diminutive of pous "foot" (see foot (n.)). Related: Pseudopodal.
pshaw (interj.) Look up pshaw at Dictionary.com
exclamation of contempt or rejection, by 1670s.
psi (n.) Look up psi at Dictionary.com
23rd letter of the Greek alphabet. Use for "psychic force, paranormal phenomenon" dates from 1942 (probably from psychic (adj.)).
psilanthropism (n.) Look up psilanthropism at Dictionary.com
"the teaching that Jesus was entirely human," 1817 (Coleridge; "Biographia Literaria"), from Greek psilanthropos "merely human," from psilos "naked, bare, mere" (see psilo-) + anthropos "man" (see anthropo-). Related: Psilanthropy; psilanthropic; psilanthropist.
psilo- Look up psilo- at Dictionary.com
before vowels psil-, word-forming element meaning "stripped, bare," from Greek psilos "bare, naked; mere," perhaps akin to psen "to rub," and both or either perhaps from PIE root *bhes- "to rub" (source also of Greek psamathos "sand;" see sand (n.)).
psilocybin (n.) Look up psilocybin at Dictionary.com
1958, from Modern Latin psilocybe, name of a Central American species of mushroom, from Greek psilos "bare" (see psilo-) + kybe "head."
psilosis (n.) Look up psilosis at Dictionary.com
"loss of hair through disease," 1837, medical Latin, from Greek psilosis "a stripping of hair," from psiloun "to strip of hair," from psilos "bare" (see psilo-).
psionic (adj.) Look up psionic at Dictionary.com
1952, from psi + ending from electronic, etc.
psittacine (adj.) Look up psittacine at Dictionary.com
"pertaining to parrots," 1826, from Latin psittacinus, from psittacus "parrot," from Greek psittakos "a parrot," said to be a foreign word.
psittacism (n.) Look up psittacism at Dictionary.com
"mere parroting, parrotry, repetition without reasoning," 1884, from French psittacisme (Liebnitz, 1765) or German psittazismus, from Latin psittacus "parrot" (see psittacine) + -ism.
psoas (n.) Look up psoas at Dictionary.com
1680s, from Greek psoa (plural psoai) "muscles of the loins." Related: Psoitis.
Gk. [psoas], the gen. of the feminine noun [psoa], was mistaken by the French anatomist Jean Riolan (1577-1657) for the nom. of a (nonexistent) masculine noun. It was he who introduced this erroneous form into anatomy." [Klein]
psoriasis (n.) Look up psoriasis at Dictionary.com
1680s, from medical Latin psoriasis, in Late Latin "mange, scurvy," from Greek psoriasis "being itchy," from psorian "to have the itch," from psora "itch, mange, scab," related to psen "to rub" (see psilo-). Related: Psoriatic.
psych Look up psych at Dictionary.com
as a noun, short for psychology in various senses (e.g. as an academic study, in student slang by 1895). As a verb, first attested 1917 as "to subject to psychoanalysis," short for psychoanalyze. From 1934 as "to outsmart" (also psych out); from 1963 as "to unnerve." However to psych (oneself) up is from 1972; to be psyched up is attested from 1968.
psyche (n.) Look up psyche at Dictionary.com
1640s, "animating spirit," from Latin psyche, from Greek psykhe "the soul, mind, spirit; breath; life, one's life, the invisible animating principle or entity which occupies and directs the physical body; understanding" (personified as Psykhe, the beloved of Eros), akin to psykhein "to blow, cool," from PIE root *bhes- "to blow, to breathe" (source also of Sanskrit bhas-), "Probably imitative" [Watkins].

Also in ancient Greek, "departed soul, spirit, ghost," and often represented symbolically as a butterfly or moth. The word had extensive sense development in Platonic philosophy and Jewish-influenced theological writing of St. Paul (compare spirit (n.)). Meaning "human soul" is from 1650s. In English, psychological sense "mind," is attested by 1910.
psychedelia (n.) Look up psychedelia at Dictionary.com
1967, from psychedelic + -ia.
psychedelic (adj.) Look up psychedelic at Dictionary.com
occasionally psychodelic, 1956, of drugs, suggested by British-born Canadian psychiatrist Humphry Osmond (1917-2004) in a letter to Aldous Huxley and used by Osmond in a scientific paper published the next year; from Greek psykhe- "mind" (see psyche) + deloun "make visible, reveal," from delos "visible, clear," from PIE root *dyeu- "to shine" (see diurnal). In popular use from 1965 with reference to anything producing effects similar to that of a psychedelic drug or enhancing the effects of such a drug. As a noun from 1956.
psychedelicize (v.) Look up psychedelicize at Dictionary.com
1966, from psychedelic + -ize. Related: Psychedelicized; psychedelicizing.
psychiatric (adj.) Look up psychiatric at Dictionary.com
1847, from French psychiatrique or else coined in English from psychiatry + -ic.
psychiatrist (n.) Look up psychiatrist at Dictionary.com
1875, from psychiatry + -ist.
A psychiatrist is a man who goes to the Folies Bergère and looks at the audience. [Anglican Bishop Mervyn Stockwood, 1961]
An older name was mad-doctor (1703); also psychiater "expert in mental diseases" (1852), from Greek psyche + iatros. Also see alienist.
psychiatry (n.) Look up psychiatry at Dictionary.com
1846, from French psychiatrie, from Medieval Latin psychiatria, literally "a healing of the soul," from Latinized form of Greek psykhe- "mind" (see psyche) + iatreia "healing, care" (see -iatric).
psychic (adj.) Look up psychic at Dictionary.com
1872, "of or pertaining to the human soul" (earlier psychical, 1640s), from Greek psykhikos "of the soul, spirit, or mind" (opposed to somatikos), also (New Testament) "concerned with the life only, animal, natural," from psykhe "soul, mind, life" (see psyche). Meaning "characterized by psychic gifts" first recorded 1871.
psychic (n.) Look up psychic at Dictionary.com
"a medium;" 1870; see psychic (adj.).
psycho (adj.) Look up psycho at Dictionary.com
1927, shortening of psychological; 1936 (Raymond Chandler) as shortening of psychopathic (adj.).
psycho (n.) Look up psycho at Dictionary.com
1925, short for psychologist; as short for psychopath from 1942.
psycho- Look up psycho- at Dictionary.com
word-forming element meaning "mind, mental; spirit, unconscious," from Greek psykho-, combining form of psykhe (see psyche). It also was used to form compounds in Greek, such as psychopates "soul-beguiling."
psycho-history (n.) Look up psycho-history at Dictionary.com
1934, from psycho- + history.
psychoactive (adj.) Look up psychoactive at Dictionary.com
also psycho-active, 1959, from psycho- + active.
psychoanalysis (n.) Look up psychoanalysis at Dictionary.com
1906, from Psychoanalyse, coined 1896 in French by Freud from Latinized form of Greek psykhe- "mental" (see psyche) + German Analyse, from Greek analysis (see analysis). Freud earlier used psychische analyse (1894).
psychoanalyst (n.) Look up psychoanalyst at Dictionary.com
also psycho-analyst, 1910; see psycho- + analyst.
psychoanalytic (adj.) Look up psychoanalytic at Dictionary.com
1902, from psychoanalysis + -ic.
psychoanalyze (v.) Look up psychoanalyze at Dictionary.com
also psycho-analyse, psychoanalyse, 1911; see psycho- + analyze. Related: Psychoanalyzed; psychoanalyzing. Earlier was psychologize (1830).
psychobabble (n.) Look up psychobabble at Dictionary.com
1976, from psycho- (representing psychology) + babble (n.). Earlier was psychologese (1961).
psychodrama (n.) Look up psychodrama at Dictionary.com
also psycho-drama, 1937 (in writing of U.S. psychiatrist Jacob L. Moreno (1889-1974)), from psycho- + drama. Related: Psychodramatic.
psychodynamic (adj.) Look up psychodynamic at Dictionary.com
also psycho-dynamic, 1856, from psycho- + dynamic (adj.).
psychogenesis (n.) Look up psychogenesis at Dictionary.com
also psycho-genesis, 1838, "origin of the soul or mind," from psycho- + genesis. Related: Psychogenetic; psychogenetical.
psychogenic (adj.) Look up psychogenic at Dictionary.com
1884, from psycho- + -genic.
psychographic (adj.) Look up psychographic at Dictionary.com
also psycho-graphic, 1856, from psychograph "supernatural photographic image," from psycho- + -graph. Related: Psychographics.
psychography (n.) Look up psychography at Dictionary.com
1883, "history of an individual soul; the natural history of the phenomenon of mind," from psycho- + -graphy. Meaning "spirit-writing" is from 1876.