1. tough guy; wild one; fearless fighter; stalwart
2. veteran (in a particular field); expert; old hand
3. person of surprising audacity; someone with a lot of nerve; brazen individual
4. (crime of) pickpocketing
police jargon; oft. written モサ
5. investigator specialized on pickpocketing; unit specialized on pickpockets
police jargon; oft. written モサ