also rollerskate, "a skate mounted on small wheels instead of iron or steel runners," 1861, American English, from roller + skate (n.2). The verb is from 1885. Related: Roller-skated; roller-skater; roller-skating.

"act of dilating," 1590s, formed from dilate on the mistaken assumption that the -ate in that word was the Latin verbal suffix (it is instead part of the stem); the proper form, dilatation, is older (c. 1400).

unit of the metric system for solid measure, 1798, from French stère "unit of volume equal to one cubic meter," from Greek stereos "solid, stiff, firm" (from PIE root *ster- (1) "stiff"). Little used, cubic meter generally serving instead.

1977, earlier retravirus (1974), from re(verse) tra(nscriptase) + connective -o- + virus. So called because it contains reverse transcriptase, an enzyme that uses RNA instead of DNA to encode genetic information, which reverses the usual pattern. Remodeled by influence of retro- "backwards."

word-forming element meaning "deputy, assistant, substitute," also "instead of, in place of," 15c., from Latin vice "in place of," ablative of vicis "a change, a turn, interchange alternation" (from PIE root *weik- (2) "to bend, to wind"). In Middle English sometimes borrowed in Old French form vis-, vi-.