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1.
When a guy looks skinny and weak but can kick some serious ass when needed.
Damn, that fool Danny looks fuckin small, but i saw him go off on Cordell the other day and man, that dude has got some spare parts.
by BUSHRULES March 09, 2005
 
2.
part stored to be available in the event of a breakdown.
the car's spare part shall be need when it is not functional
by KOL-F September 10, 2007