Definitions
1.nounA medium-sized rodent belonging to the genus Rattus.
2.nounAny of the numerous members of several rodent families (e.g. voles and mice) that resemble true rats in appearance, usually having a pointy snout, a long, bare tail, and body length greater than about 12 cm, or 5 inches.
3.nounA person who is known for betrayal; a scoundrel; a quisling."What a rat, leaving us stranded here!"
4.nounAn informant or snitch.
5.nounA scab: a worker who acts against trade union policies.
6.nounA person who routinely spends time at a particular location."He loved hockey and was a devoted rink rat."
7.nounA wad of shed hair used as part of a hairstyle.
8.nounA roll of material used to puff out the hair, which is turned over it.
9.nounVagina."Get your rat out."
10.nounShort for muskrat.
11.verb(usually with “on” or “out”) To betray a person or party, especially by telling their secret to an authority or an enemy; to turn someone in."He is going to rat us out!"
12.verbTo work as a scab, going against trade union policies.
13.verb(of a dog, etc.) To kill rats.