Wordnet 3.0
NOUN (1)
1.
the sixth month of the civil year;
the twelfth month of the ecclesiastic year in the Jewish calendar (in February and March);
The Collaborative International Dictionary of English v.0.48:
Adar \A"dar\, n. [Heb. ad[aum]r.]
The twelfth month of the Hebrew ecclesiastical year, and the
sixth of the civil. It corresponded nearly with March.
[1913 Webster]
WordNet (r) 3.0 (2006):
Adar
n 1: the sixth month of the civil year; the twelfth month of the
ecclesiastic year in the Jewish calendar (in February and
March)