You found me, but you spelled my name wrong...

The boy's name Colin \c(o)-lin\ is pronounced KAH-lin. It is of Irish, Scottish and Gaelic origin, and its meaning is "young creature". Diminutive form of the medieval name Col or Colle, a short form of Nicholas (Greek) "people of victory". In Scotland, it has been used as an Anglicised form of Cailean (Gaelic), popular among the Campbells and the MacKenzies.

The boy's name Collin \c(ol)-lin\ is pronounced KAH-lin. It is of Scottish origin. Variant of Colin.

Collin with two L's is only a variant of the original name Colin with a single L.