dormouse [LME] Dormice are not mice, although they are rodents. The exact history of the word is not entirely clear, but it is thought that that there was a now lost French name such as dormouse ‘inclined to be dormant, sleepy’, because dormice are nocturnal and hibernate, which was reinterpreted as containing the English ‘mouse’. The French would have come ultimately from Latin dormire ‘to sleep’, which is behind words such as dormant [ME] and dormitory [LME].