A Pants' or 'a Pair of Pants'. Which Is Correct?

Since the word "pants" only has a plural form, you cannot use the article "a". However, you can say "a pair of".
Since the word "pants" only has a plural form, you cannot use the article "a" or numbers with it. However, you can say "a pair of pants", "two pairs of pants", etc.

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Trousers - Wikipedia

A Trousers' or 'a Pair of Trousers'. Which Is Correct?

What's up with a “pair of pants” in English? It's just one article

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