a. 软骨的,软骨质的

Cartilaginous \Car`ti*lag"i*nous\, a. [L. cartilaginosus: cf. F.
cartilagineux.]
1. Of or pertaining to cartilage; gristly; firm and tough
like cartilage.

2. (Zo["o]l.) Having the skeleton in the state of cartilage,
the bones containing little or no calcareous matter; said
of certain fishes, as the sturgeon and the sharks.