adapter

UK: /əˈdæptə^r/ US: /əˈdæptɚ/ ,(ə dap′tər)

WordReference Random House Learner's Dictionary of American English © 2025

a•dapt•er or a•dap•tor/əˈdæptɚ/   n. [countable]

1. one that adapts.
2. Mechanical Engineering a connector for joining parts or devices having different sizes, designs, etc.

WordReference Random House Unabridged Dictionary of American English © 2025

a•dapt•er  (ə dap′tər), n. 

1. a person or thing that adapts.
2. Mechanical Engineering a connector for joining parts or devices having different sizes, designs, etc., enabling them to be fitted or to work together.
3. Mechanical Engineering an accessory to convert a machine, tool, or part to a new or modified use.
4. [Computers.] See expansion card. 

Also, a•dap′tor. 

• adapt + -er¹ 1795–1805

adapter, +n. 

1. Computing See expansion card. 

Collins Concise English Dictionary © HarperCollins Publishers::

adaptor, adapter / əˈdæptə/ noun

1. a person or thing that adapts
2. any device for connecting two parts, esp ones that are of different sizes or have different mating fitments
3. a plug used to connect an electrical device to a mains supply when they have different types of terminals
4. a device used to connect several electrical appliances to a single mains socket