in zoology, "thick-headed," by 1862, from pachy- "thick, large" + -cephalic. Related: Pachycephalous (1890).
Entries linking to pachycephalic
pachy-
word-forming element in science meaning "thick, large, massive," from Latinized form of Greek pakhys "thick, fat, well-fed, dense, stout," from PIE *bhengh- "thick, fat" (source also of Sanskrit bahu- "much, numerous;" Avestan bazah- "height, depth;" Armenian bazum "much;" Hittite pankush "large," panku- (adj.) "total;" Old Norse bingr "heap," Old High German bungo "a bulb;" Latvian biezs "thick").
-cephalic
word-forming element meaning "having a head" (of a specified type), from Greek kephalē "head" (see cephalo-).