Thornback

Noun

1. Any animal with a thorny back, especially marine animals, such as: The thornback guitarfish (Platyrhinoidis triseriata), a species of ray in the north-eastern Pacific Ocean. The thornback ray or thornback skate (Raja clavata), a species of ray in the Atlantic Ocean. The thornback skate (Dentiraja lemprieri), a fish endemic to Australia.
2. The thornback guitarfish (Platyrhinoidis triseriata), a species of ray in the north-eastern Pacific Ocean.
3. The thornback ray or thornback skate (Raja clavata), a species of ray in the Atlantic Ocean.
4. The thornback skate (Dentiraja lemprieri), a fish endemic to Australia.
5. A woman over a certain age (variously 26 or 30) who has never married, older than a spinster.