riding bitt vs bollard

riding bitt and bollard both are nouns.

Word	Noun	Adjective	Verb	Adverb
riding bitt	Yes	No	No	No
bollard	Yes	No	No	No

As nouns, bollard is a hypernym of riding bitt; that is, bollard is a word with a broader meaning than riding bitt:

riding bitt: one of the large bitts used to secure the cable of a dropped anchor
bollard: a strong post (as on a wharf or quay or ship for attaching mooring lines)

Other hypernyms of riding bitt include bitt.

riding bitt (noun)	bollard (noun)
one of the large bitts used to secure the cable of a dropped anchor	a strong post (as on a wharf or quay or ship for attaching mooring lines)