Extension Definition & Meaning | Britannica Dictionary
Britannica Dictionary definition of EXTENSION
1
:
the act of extending something: such as
a
:
the act of making something longer or greater
[noncount]
-
extension of the patient's life
[count]
-
He's asking for a contract extension.
b
:
the act of straightening or stretching something (such as an arm or a leg)
[count]
-
He did some leg extensions. [=exercises in which you extend your legs]
[noncount]
-
Make sure that the muscles get the proper amount of extension.
2
[count]
:
extra time allowed for doing something
-
I missed the deadline but was granted an extension.
3
[count]
:
something (such as an interest or activity) that develops from something else
— + of
-
Writing screenplays was a natural/logical extension of his career as a novelist and his longtime interest in film.
◊ The phrase by extension is used to say that what follows comes from or is connected with something that has already been mentioned. The new measures benefit taxpayers and, by extension, the economy. He disliked authority and, by extension, all government officials.
4
[count]
a
:
a part that is added on to something to make it larger or longer
-
They built an extension on their house.
-
a road extension
5
[count]
:
an extra telephone that is connected to the main line
-
We've added another extension in our daughter's bedroom.
also
:
a telephone number that connects to a particular extension
-
I dialed her extension, but she wasn't at her desk.
-
Extension 365, please.