n. & adj.
--n.
1. the yellowish-brown mottled or clouded outer shell of some turtles, used for decorative hair-combs, jewellery, etc.
2 a tortoiseshell cat. b tortoiseshell butterfly.
--adj. having the colouring or appearance of tortoiseshell.
Phrases and idioms:
tortoiseshell butterfly any of various butterflies, esp. of the genus Aglais or Nymphalis, with wings mottled like tortoiseshell. tortoiseshell cat a domestic cat with markings resembling tortoiseshell.