trousers

Q: Is it correct to say "This trousers is new."?

No — say "These trousers are new.". 'Trousers' is a plural noun and always takes a plural verb.

Definition

n. a piece of clothing that covers the lower part of your body, with a separate part for each leg. In American English, people usually say 'pants' instead.

n. an outer garment covering the body from the waist to the ankles, with a separate part for each leg. The term is standard in British English; 'pants' is the common equivalent in American English.

simple

“He wears black trousers to work.”

contextual

“I need to buy a new pair of trousers for the wedding this weekend.”

complex

“The tailor expertly adjusted the length of the wool trousers to ensure they had the perfect break just above the shoe.”

The noun is a plurale tantum, meaning it is always plural and takes a plural verb (e.g., 'my trousers are...'). It is counted using 'a pair of'.

This trousers is new.

These trousers are new.

'Trousers' is a plural noun and always takes a plural verb.

Attested since the 1610s, from the earlier form trouzes (attested since the 1580s), extended from trouse (1570s), with plural ending typical of things in pairs, from Middle Irish triubus (“close-fitting shorts”), from Old Irish tribus, of uncertain origin. The unexplained intrusive second -r- is perhaps due to the influence of drawers. Doublet of trews (“trousers”). Old Irish tribus is probably a borrowing of Anglo-Norman tribuz, trebuz, from Old French trebus, from Old Occitan trebucs, trabucs, from Late Latin trabrugi, tribuces, tubruci (“leg-coverings”), from an early Germanic language, likely Gothic 𐌸𐌹𐌿𐌷𐌱𐍂𐍉𐌺𐍃 (þiuhbrōks), from Proto-Germanic þeuhabrōks (“loincloth, trousers”), from Proto-Germanic þeuhą (“thigh”) + *brōks (“leggings, trousers”), thus making it by surface analysis, thigh + breeches. Cognate with Old High German diohbruoh (“loincloth, trousers”), whence obsolete German Diechbruch (“short legwear, knee breeches, loincloth”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

corduroy mouth