Entry 1 sense Webster, 1913 Duchess /dŭch'-əs/ · Duch·ess · IPA /ˈdʌt͡ʃɪs/ 01 n. The wife or widow of a duke; also, a lady who has the sovereignty of a duchy in her own right. 1. The wife or widow of a duke; also, a lady who has the sovereignty of a duchy in her own right.