churidars vs pair of trousers

churidars and pair of trousers both are nouns.

Word	Noun	Adjective	Verb	Adverb
churidars	Yes	No	No	No
pair of trousers	Yes	No	No	No

As nouns, pair of trousers is a hypernym of churidars; that is, pair of trousers is a word with a broader meaning than churidars:

churidars: tight trousers worn by people from the Indian subcontinent (typically with a kameez or kurta)
pair of trousers: (usually in the plural) a garment extending from the waist to the knee or ankle, covering each leg separately

Other hypernyms of churidars include pant, trousers.

churidars (noun)	pair of trousers (noun)
tight trousers worn by people from the Indian subcontinent (typically with a kameez or kurta)	(usually in the plural) a garment extending from the waist to the knee or ankle, covering each leg separately