mid-15c., "abundant, flowing in," in reference to occult power of the stars, etc., also of grace, from Latin influentem (nominative influens) "flowing in," present participle of influere "to flow in" (see influence (n.)). Also occasionally in the sense "influential" (1630s).
1550s, "one who engages in mental speculation," from Latin speculator "a looker-out, spy, scout, explorer; investigator, examiner," agent noun from speculari (see speculation). The financial sense is from 1778. Formerly also "observer, onlooker," especially "an occult seer" (1650s). Fem. form speculatrix attested from 1610s. Related: Speculatory.
past-participle adjective from hide (v.1); a Middle English formation (Old English had gehydd "hidden") on the model of ride/ridden, etc. As "secret, occult" from 1540s. Hidden persuaders (1957) was Vance Packard's term for ad men.
"an expert, one who has attained knowledge," especially "one who is skilled in the secrets of an occult science," 1660s, from Latin adeptus (adj.) "having attained" (see adept (adj.)). The Latin adjective was used as a noun in this sense in Medieval Latin among alchemists. It implies natural and acquired ability, whereas expert implies more of experience and practice.
early 15c., "philosopher, sage," from Middle English wys "wise" (see wise (adj.)) + -ard. Compare Lithuanian žynystė "magic," žynys "sorcerer," žynė "witch," all from žinoti "to know." The ground sense is perhaps "to know the future." The meaning "one with magical power, one proficient in the occult sciences" did not emerge distinctly until c. 1550, the distinction between philosophy and magic being blurred in the Middle Ages. As a slang word meaning "excellent" it is recorded from 1922.
1630s "dealing with occult science or alchemy," from Latin hermeticus, from Greek Hermes, god of science and art (among other things), who was identified by Neoplatonists, mystics, and alchemists with the Egyptian god Thoth as Hermes Trismegistos "Thrice-Great Hermes," who supposedly invented the process of making a glass tube airtight (a process in alchemy) using a secret seal. Hence, "completely sealed" (c. 1600, implied in hermetically).
late 14c., mistike, "spiritually allegorical, pertaining to mysteries of faith," from Old French mistique "mysterious, full of mystery" (14c.), or directly from Latin mysticus "mystical, mystic, of secret rites" (source also of Italian mistico, Spanish mistico), from Greek mystikos "secret, mystic, connected with the mysteries," from mystes "one who has been initiated" (see mystery (n.1)).
Meaning "pertaining to occult practices or ancient religions" is recorded by 1610s. That of "hidden from or obscure to human knowledge or comprehension" is by 1630s.
member of a supposed secret society possessing ancient occult wisdom, 1620s, from Modern Latin rosa crucis (DuCange) or crux, in either case a Latinization of German Rosenkreuz, French rosecroix, in either case from the name of the society's reputed founder, Christian Rosenkreuz, said to date from 1484 but not mentioned before 1614. As an adjective from 1660s. Related: Rosicrucianism.
The book describing the Rosicrucians ("Fama Fraternitatis," published in 1614) is generally regarded as merely an elaborate satire on the charlatanry and credulity of the times. Books of Rosicrucian pretensions were formerly numerous in England as well as in Germany, and several have lately reappeared in the United States. [Century Dictionary, 1895]
1590s, from French tarot (16c.), from Old Italian tarocchi (singular tarocco), a word of unknown origin, perhaps from Arabic taraha "he rejected, put aside." Originally an everyday game deck in much of Europe (though not in Britain), their occult and fortune-telling use seems to date from late 18c. and became popular in England 20c. Tarot games seem to have originated among aristocrats in northern Italy in early 15c. By early 16c. tarocchi had emerged in Italian as the name of the special cards, and by extension the whole pack; whence the French word, German Tarock, etc. The tarots are thus, strictly speaking, the 22 figured cards added to the 56-card suits pack.