Falsies is the shorter name for false eyelashes. It's always plural since they come in pairs or multiple seperate bundles. Falsies can come in a variety of different styles and be worn by anyone.
It's most common to see the word used by the beauty community. The term is sometimes used on the product themself or mascara that's supposed to replicate the look of false lashes.
Some women use falsies to appear more doll-like