Scissors is a plural noun. There are some nouns, like scissors, that only have a plural form and are grammatically plural.
"Scissors" is a plural noun. Some names of tools and instruments, like scissors, only have a plural form.
She used scissors to cut her nails.
She used a scissor to cut her nails.
Plural nouns are also known as pluralia tantum (Latin for "plural only"). They typically, but not always, involve objects that are made up of two joined parts, such as forceps, pliers, tongs, and tweezers.
Steven used his pliers to cut the wire.
If your scissors have a flat edge, you can easily sharpen them.
Remember, plural nouns take a plural verb, so we say "scissors are" (not "scissors is").
Those scissors are great for paper and thicker materials.
This scissors is great for paper and thicker materials.
While you cannot use the article "a" before plural nouns, you can introduce the phrases "a pair of scissors", "two pairs of scissors", etc. when counting these objects.
You can find two pairs of scissors in the drawer.