Caldera and Sinus

Caldera noun - A large crater caused by the violent explosion of a volcano that collapses into a depression.

Sinus and caldera are semantically related. In some cases you can use "Sinus" instead a noun "Caldera".

Sinus noun - An abnormal passage leading from a suppurating cavity to the body surface.

Caldera and sinus are semantically related. Sometimes you can use "Caldera" instead a noun "Sinus".