McSwain
A Scottish and Irish surname usually understood as a patronymic, though its exact Gaelic source is uncertain.
The #5,600 most common surname in the United States (2010 Census) — about 1 in every 49,693 Americans shares it.
Etymology
McSwain is an anglicized surname built on Gaelic Mac, meaning “son of,” but the second element is not securely established. Older surname writers sometimes linked it to a word they glossed as “lover” or to a personal name interpreted as “sage,” though those explanations are speculative and not firmly proven. In practice, the name is best treated as a patronymic form of uncertain Gaelic origin, with spelling influenced by English rendering of Scottish and Irish pronunciation.
History
The surname appears in Scottish and Irish records in several spellings, especially where Gaelic names were adapted into English orthography. In North America, McSwain became established through later migration from the British Isles, and it is now most familiar as a surname in the United States. Because of its varied spellings and uncertain Gaelic root, it is often grouped with other Mac/Mc surnames that were simplified or altered over time.
Origin
Regions
Variant spellings
Fun fact
Some 19th-century surname books tried to connect McSwain with Gaelic words meaning “lover” or “sage,” showing how inventive surname etymology could be before modern standards of evidence.
From the historical record
“Son of Charles. McSwain. Mac, son ; Scotch sivayn, genitive swayne, a lover. Son of a lover McSiveegan. Mac, son ; saoi, pronounced szvee, a sage, a philosopher; gan, offspring. Son of the descendant of a philosopher.”
— Family Names from the Irish, Anglo-Saxon, Anglo-Norman and Scotch