Merger
来自Big Physics
early 18th century: from Anglo-Norman French merger (verb used as a noun): see merge.
wiktionary
From merge + -er.
Anglo-Norman merger(verb used as noun)
etymonline
merger (n.)
1728 in legal sense, "extinguishment by absorption," originally of real estate titles, from merge (v.), on analogy of French infinitives used as nouns (see waiver). From 1889 in the business sense "extinguishment of a security for a debt by the creditor's acceptance of a higher security;" not common until c. 1926. General meaning "any act of merging" is by 1881.