( mousier, mousiest), mousey [adjective] [disapproving]I'm fed up with having such mousy (= plain pale brown) hair - I'm going to dye it blonde.(figurative) I wasn't able to see the manager - just her mousy (= nervous, quiet and shy) little assistant.
MOUSY
Meaning of MOUSY in English
Cambridge English vocab. Кембриджский английский словарь. 2012