Used other than figuratively or idiomatically: see cat, claw.
Uncaria tomentosa, a plant species found in the tropical jungles of South and Central America
Biancaea decapetala, a thorny evergreen shrub of India
Acacia plumosa, a medicinal plant species native to Brazil
Grevillea alpina, a shrub species native to Australia
Carpobrotus edulis, or uña de gato (Spanish: "cat's claw"), a plant species in the Aizoaceae family
Mimosa nuttallii (formerly Schrankia nuttalli), a plant native to the Midwestern United States
Dolichandra unguis-cati, or cat's claw creeper, a Central American climbing vine of the Bignoniaceae family
Uncaria rhynchophylla, a plant species used in traditional Chinese medicine
bayag-kambing (Caesalpinia crista)
Martynia annua, a plant species endemic to Brazil
Senegalia greggii, formerly Acacia greggii, a tree species native to the southwestern United States and northern Mexico
Uncaria guianensis, a plant species found in Guyana
Motherfucker (usually in similes, e.g. "like a mug" or "as a mug")
A stupid or contemptible person.
A gullible or easily-cheated person.
The face.
A criminal.
A large cup for beverages, usually having a handle and used without a saucer.
Uninteresting or unpleasant.
To assault for the purpose of robbery.
To photograph for identification; to take a mug shot.
To exaggerate a facial expression for communicative emphasis; to make a face, to pose, as for photographs or in a performance, in an exaggerated or affected manner.
To learn or review a subject as much as possible in a short time; cram.