weir vs fencing

weir and fencing both are nouns.

Word	Noun	Adjective	Verb	Adverb
weir	Yes	No	No	No
fencing	Yes	No	No	No

As nouns, fencing is a hypernym of weir; that is, fencing is a word with a broader meaning than weir:

Other hypernyms of weir include fence.

weir (noun)	fencing (noun)
a low dam built across a stream to raise its level or divert its flow	the art or sport of fighting with swords (especially the use of foils or epees or sabres to score points under a set of rules)
a fence or wattle built across a stream to catch or retain fish	a barrier that serves to enclose an area
	material for building fences