Coomer
Likely a spelling variant of Cope or Cooper, probably originally referring to a seller of cups or a place-name-based nickname.
The #7,668 most common surname in the United States (2010 Census) — about 1 in every 71,287 Americans shares it.
Etymology
The evidence for Coomer is thin, but it is likely an English surname that developed as a spelling variant of names such as Cope or Cooper. In older records, spellings were often highly fluid, and a final -er ending could be added or shifted in pronunciation over time. If linked with Cope, the name may go back to an old word for a cloak or cope; if linked with Cooper, it would point to the trade of making or dealing in barrels and tubs.
History
The surname appears in English records in forms that overlap with Cope and related variants, which makes its separate history hard to trace cleanly. In modern usage it is most familiar in the United States, where it remains relatively uncommon but established. The spelling Coomer may reflect regional pronunciation or later clerical standardization rather than a completely separate origin.
Origin
Regions
Variant spellings
Fun fact
Nineteenth-century surname dictionaries often treated Coomer as part of a wider family of Cope/Cooper-like spellings rather than as an isolated name.
From the historical record
“179a. Married— John Ball and Mary Coomer: ibkL ii. 75. London, 6, o ; New York, o, i. Coope, Coop.— Local, *at the cope ' ; V. Cope.”
— A Dictionary of English and Welsh Surnames (alternate scan)