extender

American  

[ik-sten-der] / ɪkˈstɛn dər /

noun

1. a substance added to another substance, as to paint or food, to increase its volume or bulk.

   to add cereal and soy protein to hamburger as extenders.

2. Photography. converter8

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extender British  

/ ɪkˈstɛndə /

noun

1. a person or thing that extends

2. a substance, such as French chalk or china clay, added to paints to give them body and decrease their rate of settlement

3. a substance added to glues and resins to dilute them or to modify their viscosity

4. a substance added to elastomers to assist the plasticizer

5. printing the part of certain lower-case letters that extends either above (the ascender) or below (the descender) the body of the letter

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Etymology

Origin of extender

First recorded in 1605–15; extend + -er ¹

Example Sentences

The all-terrain buggy she uses to herd cattle is fitted with an internet extender, enabling her to message friends on Snapchat while working.

From BBC • Dec. 10, 2025

Squish factor: The off-road Jeep tour didn’t have a seatbelt extender, so I had to sit in the front seat to fit comfortably.

From Salon • Oct. 23, 2024

The gate agent hands Garris an extra boarding pass, she walks onto the plane, asks for a seat-belt extender, takes a window seat and places the extra boarding pass in the middle seat.

From Los Angeles Times • Dec. 20, 2023

Gemini marries LFP cells similar to those used in the Aries pack with higher-energy cells that act as a range extender as charge is depleted.

From Reuters • Aug. 15, 2023

Golly sits up and pushes the leg extender down.

From "Odd One Out" by Nic Stone