From The Collaborative International Dictionary of English v.0.48 [gcide]:
Unmanly \Unmanly\
See manly.
From WordNet (r) 3.0 (2006) [wn]:
unmanly
adv 1: without qualities thought to befit a man [syn:
unmanfully, unmanly] [ant: manfully, manly]
adj 1: not possessing qualities befitting a man [syn: unmanly,
unmanful, unmanlike] [ant: manful, manlike,
manly]
2: lacking in courage and manly strength and resolution;
contemptibly fearful [syn: pusillanimous, poor-spirited,
unmanly]