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.

Pair Nouns and the indefinite article

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