Ferret

Ferret \FER-it\ , verb;
1. To search out, discover, or bring to light
2. To drive out by using or as if using a ferret
3. To harry, worry, or torment
noun;
1. Domesticated, usually red-eyed, and albinic variety of the polecat
2. A narrow tape or ribbon, as of silk or cotton, used for binding, trimming, etc.

According to Etymonline.com:
This noun dates to the late 14th century and comes from Old French furet, which is a diminutive version of fuiron ("weasel, ferrit" literally "thief"). The Old French word probably comes from Late Latin furionem (related to furonem, "cat" or "robber") from Latin fur (genitive is furis and it means "thief"). In the early 15th century this word was used to refer to half-tamed ferrets used to kill rats and flush rabbits from burrows, which extended the sense of the word to "search out, discover" in the 1570's. The sense of "worry" is related to the hunting definition because if you are "hunting after" something you "worry" about it.

*Today's word and the first definition were both taken from Dictionary.com's 'Word of the Day' for Monday, December 20