[f. LAMB v. + -ING2.] Of a ewe: Breeding, with young.
1861. Times, 24 Sept., 7/6. Some [roots are] carted to lambing ewes on the pastures.
1883. Pall Mall Gaz., 17 March, 4/1. They smash the farmer’s gates, level his fences … frighten the lambing ewes.
