enlighten (v.)youdaoicibaDictYouDict
late 14c., "to remove the dimness or blindness" (usually figurative, from one's eyes or heart); see en- (1) + lighten. From 1660s as "supply with intellectual light." Literal senses are later and less common in English: "put light in" is from 1580s; "shed light upon" is from 1610s. Related: Enlightened; enlightening. Old English had inlihtan "to illuminate, enlighten."
hit (v.)youdaoicibaDictYouDict
late Old English hyttan, hittan "come upon, meet with, fall in with, 'hit' upon," from a Scandinavian source such as Old Norse hitta "to light upon, meet with," also "to hit, strike;" Swedish hitta "to find," Danish and Norwegian hitte "to hit, find," from Proto-Germanic *hitjan, of uncertain origin. Related: Hitting. Meaning shifted in late Old English period to "strike," via "to reach with a blow or missile," and replaced Old English slean in this sense. Original sense survives in phrases such as hit it off (1780, earlier in same sense hit it, 1630s) and is revived in hit on (1970s).

Underworld slang meaning "to kill by plan" is 1955 (as a noun in this sense from 1970). To hit the bottle "drink alcohol" is from 1889. To hit the nail on the head (1570s) is from archery. Hit the road "leave" is from 1873; to hit (someone) up "request something" is from 1917. Hit and run is 1899 as a baseball play, 1924 as a driver failing to stop at a crash he caused. To not know what hit (one) is from 1923.
irradiate (v.)youdaoicibaDictYouDict
c. 1600, "to cast beams of light upon," from Latin irradiatus, past participle of irradiare "shine forth," from assimilated form of in- "into, in" (see in- (2)) + radiare "to shine" (see radiate). Meaning "expose to radiation other than light" (originally X-rays) is from 1901. Related: Irradiated; irradiating.
lighten (v.2)youdaoicibaDictYouDict
"shed light upon, illuminate, brighten," early 14c., from light (n.) -en (1). Meaning "to grow brighter" is late 14c. Of faces, expressions, etc., from 1795. Related: Lightened; lightening.
tilt (v.2)youdaoicibaDictYouDict
"to joust," 1590s, from tilt (n.1). Related: Tilted; tilting. The figurative sense of tilting at windmills is suggested in English by 1798; the image is from Don Quixote, who mistook them for giants.
So saying, and heartily recommending himself to his lady Dulcinea, whom he implored to succour him in this emergency, bracing on his target, and setting his lance in the rest, he put his Rozinante to full speed, and assaulting the nearest windmill, thrust it into one of the sails, which was drove about by the wind with so much fury, that the lance was shivered to pieces, and both knight and steed whirled aloft, and overthrown in very bad plight upon the plain. [Smollett translation, 1755]