Paleocene (adj.)

before vowels pale- word-forming element used in scientific combinations (mostly since c. 1870) meaning "ancient, early, prehistoric, primitive, fossil," from Latinized form of Greek palaios "old, ancient," from palai "long ago, far back" (from PIE root *kwel- (2) "far" in space or time).

early 15c., "recently made," of foods, etc., "fresh, newly made," from Latin recentem (nominative recens) "lately done or made, of recent origin, new, fresh, young," from re- (see re-) + PIE root *ken- "fresh, new, young" (source also of Greek kainos "new;" Sanskrit kanina- "young;" Old Irish cetu- "first," Breton kent "earlier;" Old Church Slavonic načino "to begin," koni "beginning").

Meaning "of or pertaining to the time just before the present" is by 1620s. Related: Recently; recentness ("state or quality of being recent," 1670s, but OED reports recency (1610s) was "Common in 19th c.").