Tom
A surname that usually began as a pet form of Thomas, especially in medieval England.
The #3,452 most common surname in the United States (2010 Census) — about 1 in every 29,830 Americans shares it.
Etymology
Tom is most commonly a short form of the personal name Thomas, which ultimately comes from an Aramaic word meaning “twin.” In surname use, it could identify someone as “Tom’s son” or simply as a family descended from a man called Tom. Some 19th-century writers also noted related forms such as Tomkin and Tomlinson, built from the same nickname base.
History
The name appears in English records through the common medieval habit of turning popular given names into hereditary surnames. Because Tom was such a familiar nickname, it generated a wide cluster of related surnames, including Tomkin, Tomkins, Tomlin, and Tomlinson. In some regions, especially in older English dialects, these names could become fixed family names fairly early.
Origin
Regions
Variant spellings
Fun fact
Tom is one of those surnames that started life as an everyday nickname before becoming a hereditary family name.
From the historical record
“TOLSON, Toll's Son : v. ToM. TOM, like Thorn, a dim. of Thomas, q.v. TOMALIN for Tomlin, q.v. TOMAN (Eng.) a syncopated form of Tolman, q.v. (Celt.) a nickname f. the Ir. toman, a 'bush,' a 'tuff. TOMBLESON, like Tombllnson, with intrus. b for Tomlinson, q.v.”
— Surnames of the United Kingdom: a concise etymological dictionary (2 vols in 1)