1955, a linguist's word, from hypo- + second element from Greek onyma "name" (from PIE root *no-men- "name"), with abstract noun ending. The relationship between two words where one may invariably be replaced by the other without changing the sense but not vice versa.

city in Texas, U.S., settled 1841, named 1846 for George M. Dallas (1792-1864), U.S. vice president under Polk (1845-49). The family name (13c.) is from the barony of Dallas (Moray) or means "dweller at the house in the dale."

1700, "a descent or plunge headfirst, a sudden attack or swoop," from dive (v.). Colloquial sense of "disreputable place of resort for drinking and vice" is  recorded in American English by 1871, perhaps because they typically were in basements, and going into one was both a literal and figurative "diving."

"visit slums of a city," especially for diversion or amusement, often under guise of philanthropy, 1884, from slum (n.). A pastime popularized by East End novels. Earlier it meant "to visit slums for disreputable purposes or in search of vice" (1860). Related: Slumming.

early 15c., relapsen, "renounce" (a vice, etc.), a sense now obsolete; 1560s as "fall into a former (bad) state or practice," from Latin relapsus, past participle of relabi "slip back, slide back, sink back," from re- "back" (see re-) + labi "to slip" (see lapse (n.)). Related: Relapsed; relapsing.

rhetorical substitution of an epithet for a proper name (or vice versa; as in His Holiness for the name of a pope), 1580s, from Latin, from Greek antonomasia, from antonomazein "to name instead, call by a new name," from anti "instead" (see anti-) + onomazein "to name," from onoma "name" (from PIE root *no-men- "name"). Related: Antonomastic.