1680s, "aware of one's action or oneself," a word of the English Enlightenment (Locke was using it by 1690, along with self-consciousness "state of being aware of oneself, consciousness of one's own identity"), from self- + conscious. The morbid sense of "preoccupied with one's own personality, conscious of oneself as an object of observation to others" is attested by 1834 (J.S. Mill). Related: Self-consciously.
c. 1400, "having a sharp point; producing punctures," senses now rare or obsolete, from Medieval Latin punctualis, from Latin punctus "a pricking" (from nasalized form of PIE root *peuk- "to prick").
The meaning "prompt" is recorded by 1670s, from the notion of "exact, precise, insisting on fine points," including the observation of time and the keeping of appointments (c. 1600). Related: Punctually.
c. 1600, "attentive in perceiving or taking notice, characterized by good powers of observation," also "attentive in observing what is prescribed or required" (a law, custom, etc.), from observe + -ant, or else from French observant, past participle of observer (see observance). In reference to Judaism, "strict in acting in accordance with precepts," from 1902. As a noun from late 15c. Related: Observantly; observantness.
"star that suddenly increases in brightness then slowly fades," 1877, from Latin nova, fem. singular adjective of novus "new" (see new), used with stella "star" (a feminine noun in Latin) to describe a new star not previously known (Tycho Brahe's published observation of the nova in Cassiopeia in 1572 was titled De nova stella). Not distinguished from supernovae until 1930s (Tycho's star was a supernova). The classical plural is novae.
1650s, "preliminary observation," especially "a learned preamble or introductory discourse prefixed to a book," from Greek prolegomenon, noun use of neuter passive present participle of prolegein "to say beforehand," from pro "before" (see pro-) + legein "to speak" (from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')") + suffix -menos (as in alumnus). The same sense is in preface (n.). Related: Prolegomenary; prolegomenous. Plural prologomena.
late 14c., "careful observation of one's surroundings, attention to details and probable consequences" (with a view to choosing the safest course), from Old French circumspection (Modern French circonspection), from Latin circumspectionem (nominative circumspectio) "a looking around; foresight, caution," noun of action from past participle stem of circumspicere "to look around," from circum "around, round about" (see circum-) + specere "to look" (from PIE root *spek- "to observe").
Of persons, "having an honest reputation" from 1755; the sense of "moderately well-to-do and deserving respect for morality; occupying a fairly good position in society" is by 1800. From 1755 as "considerable in size or number;" from 1775 as "not too big, tolerable, fair, mediocre." Related: Respectably.
"arranger of sexual liaisons, one who caters for the lusts of others," 1520s, "procurer, pimp," from Middle English Pandare (late 14c.), used by Chaucer ("Troylus and Cryseyde"), who borrowed it from Boccaccio (who had it in Italian form Pandaro in "Filostrato") as name of the prince (Greek Pandaros), who procured the love of Cressida (his niece in Chaucer, his cousin in Boccaccio) for Troilus. The story and the name are medieval inventions. The name turns up in ancient Greek, but without the story; in Homer he is a Lycian participant in the Trojan War. The name is thus perhaps non-Greek. Spelling in English was influenced by the agent-noun suffix -er.
mid-14c., "action of observing or testing; an observation, test, or trial;" also "piece of evidence or empirical proof; feat of magic or sorcery," from Old French esperment "practical knowledge, cunning; enchantment, magic spell; trial, proof, example; lesson, sign, indication," from Latin experimentum "a trial, test, proof, experiment," noun of action from experiri "to try, test," from ex "out of" (see ex-) + peritus "experienced, tested," from PIE *per-yo-, suffixed form of root *per- (3) "to try, risk."