Duenna \Du*en"na\, n.; pl. {Duennas}. [Sp. due[~n]a, do[~n]a, fr. L. domina. See {Dame}.] 1. The chief lady in waiting on the queen of Spain. --Brande. 2. An elderly lady holding a station between a governess and companion, and appointed to have charge over the younger ladies in a Spanish or a Portuguese family. --Brande & C. 3. Any old woman who is employed to guard a younger one; a governess. --Arbuthnot.