What is the meaning of Nasus?

A horn-like elongated rostrum on the head of soldier termites of the subfamily Nasutiterminae, capable of producing and spraying noxious secretions for defense.

A prolongation on the front of the head of a cranefly.

The nose.

The sense of smell.

The projecting part of a vessel; the spout or nozzle.

Source: wiktionary.org