Lamb/læm/ Definition 1 of 5Pro Tip 1/3Age Sensitive Used for sheep under one year old. Older sheep are not called lambs. The spring lambs were frolicking in the field. Pro Tip 2/3Farm Animal Often associated with pastoral scenes and farm life. Children enjoy seeing lambs during farm visits. Pro Tip 3/3Symbol of Innocence Lambs often symbolize purity and innocence in literature and art. The lamb in the painting represented innocence.