Son of Colin or little whelp
Kollen is a rare variant of the Gaelic name Colin or the Scandinavian name Kollen. It likely derives from the Middle English 'col' meaning charcoal or the Gaelic 'cailean' meaning young dog or pup. In some contexts, it functions as a patronymic surname meaning 'son of Kol'.
Less common today
Kollen isn't in the latest US Top 1000. It last peaked at #5,611 in 2001.
US births per 5-year period, 1990βpresent (SSA data).