Key

Part of speech: noun, verb, adjective

Pronunciation: /kiː/

Definitions

1. A tool designed to operate mechanical fasteners like locks ; a fundamental component that enables entry or comprehension ; a significant fact that clarifies or resolves a problem
2. An instrument used to unlock mechanisms ; an essential piece of knowledge that provides understanding ; a solution or method that grants access or ability to control something
3. A device crafted to open locks or fastenings ; a crucial idea or piece of information needed to grasp or solve an issue ; a means by which something can be accessed or achieved

Etymology: Medieval keys were not the small metal tools in a pocket. They were long poles ending in a hook, used to lift a crossbar that blocked a door from the inside, reached through a hole in the door from outside. The earliest sense may have been even simpler. The linguist Anatoly Liberman suggested the original meaning was probably a pin with a twisted end. The word came into Middle English as "kaye" and "keiȝe," from a shared Anglo-Frisian ancestor whose origin is uncertain. Its closest surviving relatives are in Frisian, such as West Frisian "kaai" and North Frisian "kai." One possible link is to a Proto-Germanic word for a stake or pole, which would fit the long wooden tool that came first.

Synonyms: unlock, crucial, essential

Antonyms: irrelevant, unimportant