Other forms: extensions
An extension is the act of getting more time, space, or length, like an extension of a deadline that gives you one more day to turn in a paper, or extensions that make your hair look longer.
The noun extension comes from the Latin word extendere, meaning “stretch out.” If you’re a great gymnast, you probably have amazing extension — flexible and long-reaching limbs. If someone meets your sister and assumes you will be exactly like her, you might say, "That's a stretch," meaning this person has, by extension, drawn conclusions about you which are somewhat true but not completely accurate.