Cain \cain\ as a boy's name (also used as girl's name Cain), is pronounced kayn. It is of Hebrew origin, and the meaning of Cain is "something produced; spear". Biblical: Cain, the firstborn son of Adam and Eve, killed his brother in jealous anger and spent the rest of his life as a wanderer in exile. Has a different source from the homonym Kane.
For more information, see also the related name Caine.