hidage (n.)

a measure of land (obsolete), Old English hid "hide of land," earlier higid, from hiw- "family," from or related to hiwan "household," hiwo "a husband, master of a household," from Proto-Germanic *hiwido-, from PIE *keiwo- (source also of Latin civis "citizen"), from PIE root *kei- (1) "to lie," also forming words for "bed, couch," and with a secondary sense of "beloved, dear."

The notion was of "amount of land needed to feed one free family and dependents," usually 100 or 120 acres, but the amount could be as little as 60, depending on the quality of the land. Often also defined as "as much land as could be tilled by one plow in a year." Translated in Latin as familia.

word-forming element in nouns of act, process, function, condition, from Old French and French -age, from Late Latin -aticum "belonging to, related to," originally neuter adjectival suffix, from PIE *-at- (source of Latin -atus, past participle suffix of verbs of the first conjugation) + *-(i)ko-, secondary suffix forming adjectives (see -ic).