Old English lamb "lamb," from Proto-Germanic *lambaz (cognates: Old Norse, Old Frisian, Gothic lamb, Middle Dutch, Dutch lam, Middle High German lamp, German Lamm "lamb"). Common to the Germanic languages, but with no certain cognates outside them. Old English plural was lomberu. Applied to persons (especially young Church members, gentle souls, etc.) from late Old English. Also sometimes used ironically for cruel or rough characters (such as Kirke's Lambs in wars of 1684-86). Lamb's-wool (adj.) is from 1550s.