Coal town or settlement of Colt
Coltin is a modern spelling variation of Colton. It originates from an English surname meaning a town where coal was found or a settlement associated with young horses (colts).
Less common today
Coltin isn't in the latest US Top 1000. It last peaked at #1,167 in 2001.
US births per 5-year period, 1990βpresent (SSA data).