Effin is not commonly used as a baby boy name. It is not in the top 1000 names. Out of the family of boy names directly related to Effin, Ethan was the most widely used in 2012.
Baby names that sound like Effin include Eban (Hebrew), Ebben, Eben (English, Hebrew, and Welsh), Ebenn, Ebin, Ebun, Efan, Efen, Effon, Efon, Evaan (Ukrainian), Evaine, Evan (Scottish, English, and Welsh), Evann, Even (Hebrew and Scandinavian), Evin (Scandinavian and English), Evon, Evyn, Eyvan, and Aodhfin (English and Gaelic).
† approx English pronunciation for Effin: EH as in "ebb (EH.B)" ; F as in "fee (F.IY)" ; IH as in "it (IH.T)" ; N as in "knee (N.IY)"