stretch out over a distance, space, time, or scope; run or extend between two points or beyond a certain point
"Service runs all the way to Cranbury"
"His knowledge doesn't go very far"
"My memory extends back to my fourth year of life"
"The facts extend beyond a consideration of her personal assets"
thrust or extend out
"He held out his hand"
"point a finger"
"extend a hand"
"the bee exserted its sting"
extend or stretch out to a greater or the full length
"Unfold the newspaper"
"stretch out that piece of cloth"
"extend the TV antenna"
To increase in extent.
"As the river floods, it extends far beyond its usual banks to cover the nearby fields."
In plain English: To extend means to make something longer, wider, or more available than it was before.
"Please extend your hand so I can shake it."
Usage: Use extend to mean making something longer or reaching out toward someone, such as extending an invitation or extending a deadline. Avoid using it when you simply want to say that something has grown bigger on its own without an active effort to reach further.
The word extend comes from the Latin verb extendō, which means "to stretch out." It entered English through Anglo-Norman and Middle French before becoming part of our modern vocabulary.