EndymionyoudaoicibaDictYouDict
beautiful youth, son of Jupiter and Calyce, beloved by Moon-goddess Selene, from Greek, perhaps literally "diver, plunger," from endyein "to enter into, sink into, plunge, dive," which was used in reference to the sun or stars setting into the sea. On this theory, he originally was a solar deity, a personification of the setting sun.
gulch (n.)youdaoicibaDictYouDict
"deep ravine," 1832, perhaps from obsolete or dialectal verb gulsh "sink in" (of land), "gush out" (of water), from Middle English gulchen "to gush forth; to drink greedily" (c. 1200). Compare gulche-cuppe "a greedy drinker" (mid-13c.). "There appears to be no etymological connection with gully" [Century Dictionary].
merge (v.)youdaoicibaDictYouDict
1630s, "to plunge or sink in," from Latin mergere "to dip, dip in, immerse, plunge," probably rhotacized from *mezgo, from PIE *mezg- "to dip, plunge" (cognates: Sanskrit majjati "dives under," Lithuanian mazgoju "to wash"). Legal sense of "absorb an estate, contract, etc. into another" is from 1726. Related: Merged; merging. As a noun, from 1805.
plunge (v.)youdaoicibaDictYouDict
late 14c., "to put or thrust violently into," also intransitive, from Old French plongier "plunge, sink into; plunge into, dive in" (mid-12c., Modern French plonger), from Vulgar Latin *plumbicare "to heave the lead," from Latin plumbum "lead" (see plumb (n.)). Original notion perhaps is of a sounding lead or a fishing net weighted with lead. Related: Plunged; plunging. Plunging neckline attested from 1949.
punch (n.3)youdaoicibaDictYouDict
"a quick blow with the fist," by 1570s, probably from punch (v.). In early use also of blows with the foot or jabs with a staff or club. Originally especially of blows that sink in to some degree ("... whom he unmercifully bruises and batters from head to foot: here a slap in the chaps, there a black eye, now a punch in the stomach, and then a kick on the breech," "Monthly Review," 1763). Figurative sense of "forceful, vigorous quality" is recorded from 1911. To beat (someone) to the punch in the figurative sense is from 1915, a metaphor from boxing (attested by 1913). Punch line (also punch-line) is from 1915 (originally in popular-song writing); punch-drunk is from 1915 (alternative form slug-nutty is from 1933).
slump (v.)youdaoicibaDictYouDict
1670s, "fall or sink into a muddy place," probably from a Scandinavian source such as Norwegian and Danish slumpe "fall upon," Swedish slumpa; perhaps ultimately of imitative origin. Related: Slumped; slumping.
The word "slump," or "slumped," has too coarse a sound to be used by a lady. [Eliza Leslie, "Miss Leslie's Behaviour Book," Philadelphia, 1839]
Economic sense from 1888.