"unequaled, unmatched," c. 1300, from peer (n.) + -less.
Entries linking to peerless
peer n.
c. 1300, "an equal in rank, character, or status" (early 13c. in Anglo-Latin), from Anglo-French peir, Old French per (10c.), from Latin par "equal" (see par (n.)). Sense of "a nobleman of especial dignity" (late 14c.) is from Charlemagne's Twelve Peers in the old romances, who, like the Arthurian knights of the Round Table, originally were so called because all were equal. Sociological sense of "one of the same age group or social set" is from 1944. Peer review "evaluation of a scientific project by experts in the relevant field" is attested by 1970. Peer pressure is recorded by 1971.
-less
word-forming element meaning "lacking, cannot be, does not," from Old English -leas, from leas "free (from), devoid (of), false, feigned," from Proto-Germanic *lausaz (cognates: Dutch -loos, German -los "-less," Old Norse lauss "loose, free, vacant, dissolute," Middle Dutch los, German los "loose, free," Gothic laus "empty, vain"), from PIE root *leu- "to loosen, divide, cut apart." Related to loose and lease.