snitch 
(snĭch) Slang
(snĭch) Slang v. snitched, snitch·ing, snitch·es
v.intr.
To act as an informer: He snitched on his comrades.
v.tr.
To steal (something, usually something of little value); pilfer: snitched a cookie from the counter.
n.
1. An informer.
2. A thief.
[Origin unknown.]
snitcher n.