zealot (n.)

early 14c., “member of a militant 1st century Jewish sect which fiercely resisted the Romans in Palestine,” from Late Latin zelotes, from Greek zēlōtēs “one who is a zealous follower,” from zēloōn “to be zealous,” from zēlos “zeal” (see zeal). Extended sense of “a fanatical enthusiast” first recorded 1630s (earlier in this sense was zelator, mid-15c.).

earnest (adj.)

from Old English eornoste (adj.) “zealous, serious,” or from Old English noun eornost “seriousness, serious intent” (surviving only in the phrase in earnest), from Proto-Germanic *er-n-os-ti- (source also of Old Saxon ernust, Old Frisian ernst, Old High German arnust “seriousness, firmness, struggle,” German Ernst “seriousness;” Gothic arniba “safely, securely;” Old Norse ern “able, vigorous,” jarna “fight, combat”), perhaps from PIE root *er- (1) “to move, set in motion.” The proper name Ernest (literally “resolute”) is from the same root. Related: Earnestness.

burgeon (v.)

early 14c., “grow, sprout, blossom,” from Anglo-French burjuner, Old French borjoner “to bud, sprout,” from borjon “a bud, shoot, pimple” (Modern French bourgeon), a word of uncertain origin. Perhaps from Vulgar Latin *burrionem (nominative *burrio), from Late Latin burra “flock of wool,” itself of uncertain origin. Some sources (Kitchin, Gamillscheg) say either the French word or the Vulgar Latin one is from Germanic (compare Old High German burjan “to raise, lift up”). The English verb is perhaps instead a native development from burjoin (n.) “a bud” (c. 1300), from Old French. According to OED, it died out by 18c. except as a technical term in gardening, and was revived early 19c. in poetry. Related: Burgeonedburgeoning.

pantheon (n.)

early 15c., Panteon “the Pantheon in Rome,” from Latin Pantheon, name of a temple dedicated to all the gods built in Rome c. 25 B.C.E. by Agrippa (since 609 C.E. made into the Christian church of Santa Maria Rotonda), from Greek Pantheion (hieron) “(shrine) of all the gods,” from pantheion, neuter of pantheios, from pan- “all” (see pan-) + theios “of or for the gods,” from theos “god” (from PIE root *dhes-, forming words for religious concepts). In reference to any group of exalted persons from 1590s.

aesthetic (n.)

1798, from German Ästhetisch (mid-18c.) or French esthétique (which is from German), ultimately from Greek aisthetikos “of or for perception by the senses, perceptive,” of things, “perceptible,” from aisthanesthai “to perceive (by the senses or by the mind), to feel,” from PIE *awis-dh-yo-, from root *au- “to perceive.”

Popularized in English by translations of Kant and used originally in the classically correct sense “science which treats of the conditions of sensuous perception” [OED]. Kant had tried to reclaim the word after Alexander Baumgarten had taken it in German to mean “criticism of taste” (1750s), but Baumgarten’s sense attained popularity in English c. 1830s (despite scholarly resistance) and freed the word from philosophy. Walter Pater used it (1868) to describe the late 19c. movement that advocated “art for art’s sake,” which further blurred the sense. [Whewell had proposed callesthetics for “the science of the perception of the beautiful.”]

As an adjective by 1798 “of or pertaining to sensual perception;” 1821 as “of or pertaining to appreciation of the beautiful.” Related: Aesthetically.

glib (adj.)

1590s, “smooth and slippery,” a dialect word, possibly a shortening of obsolete glibbery “slippery,” which is perhaps from Low German glibberig “smooth, slippery,” from Middle Low German glibberich, from or related to glibber “jelly,” all part of the Germanic group of gl- words for “smooth, shining, joyful,” from PIE root *ghel- (2) “to shine.” Of words, speakers, etc., from c. 1600. Related: Gliblyglibness.