Definition of "rat"
A medium-sized rodent belonging to the genus Rattus.
A term indiscriminately applied to numerous members of several rodent families (e.g. voles and mice) having bodies longer than about 12 cm, or 5 inches.
A person who is known for betrayal; a scoundrel; a quisling.
An informant or snitch.
To betray someone and tell their secret to an authority or an enemy; to turn someone in, bewray.
To kill rats.