Denshi Jisho — Online Japanese dictionary

勿 まな must not; may not
Noun, Archaism 
勿れ なかれ must not; do not
Particle 
勿怪 もっけ unexpected
No-adjective, Na-adjective, Noun, Usually written using kana alone 
勿論 もちろん of course; certainly; naturally
Common word, Adverb, Usually written using kana alone 
勿吉 もっきつ Mohe (one of the Tungusic-speaking tribes)
Noun, Archaism 
勿体 もったい 1: superior airs; air of importance;
2: overemphasis
Noun 
勿忘草 わすれなぐさ forget-me-not (esp. the water forget-me-not, Myosotis scorpioides)
Noun 
勿体ない もったいない 1: (Usually written using kana alone) impious; profane; sacrilegious;
2: too good; more than one deserves; unworthy of;
3: wasteful
Common word, Adjective 
勿体無い もったいない 1: (Usually written using kana alone) impious; profane; sacrilegious;
2: too good; more than one deserves; unworthy of;
3: wasteful
Adjective 
勿体ぶる もったいぶる to put on airs; to assume importance
Godan verb with ru ending, Intransitive verb 
勿体振る もったいぶる to put on airs; to assume importance
Godan verb with ru ending, Intransitive verb 
勿怪の幸い もっけのさいわい windfall; piece of good luck
Expression 
勿れ主義の道徳 なかれしゅぎのどうとく negative virtues
Noun 

You can also

Look up kanji details for 勿.

Try a Yahoo Jisho search for 勿 .
Try a Goo Jisho search for 勿 .
Try a Google search for 勿 .