1520s, "adultery as affecting the honor of the husband," from cuckold (n.) + -ery.
Entries linking to cuckoldry
cuckold n.
derisive name for a man whose wife is false to him, "husband of an adulteress," early 13c., kukewald, cokewold, from Old French cucuault, from cocu (see cuckoo) + pejorative suffix -ault, of Germanic origin. So called from the female bird's alleged habit of changing mates, or her authentic habit of leaving eggs in another bird's nest.
In Modern French the identity is more obvious: Coucou for the bird and cocu for the betrayed husband. German Hahnrei (13c.), from Low German, is of obscure origin. The second element seems to be connected to words for "ardent," and suggests perhaps "sexually aggressive hen," with transferal to humans, but Kluge suggests rather a connection to words for "capon" and "castrated." The female equivalent, cuckquean, is attested by 1560s.
-ery
word-forming element making nouns meaning "place for, art of, condition of, quantity of," from Middle English -erie, from Latin -arius (see -ary). Also sometimes in modern colloquial use "the collectivity of" or "an example of."