Origin: Latin suffix -able
Adjustable has 4 different meanings across 1 category:
Anything that can be adjusted.
"The adjustable headband on my new hat lets me change its size to fit comfortably over my curly hair."
In plain English: An adjustable is something that can be changed to fit different needs or sizes.
"The adjustable on his bike allows him to change the seat height easily."
Usage: The word "adjustable" functions only as an adjective and should never be used as a noun in standard English. Instead of saying "the adjustable," refer to the specific item itself, such as "the adjustment" or "the setting."
capable of being adjusted
"The headrest on my new office chair is adjustable, so I can set it to the perfect height for my posture."
In plain English: Adjustable means something that can be changed to fit different needs or sizes.
"The chair has adjustable legs so you can set it to the perfect height."
Usage: Use adjustable to describe an object that can be changed in size, shape, or position to fit specific needs, such as an adjustable chair or clock. Avoid using it for abstract concepts like feelings or opinions, which cannot physically be modified.
The word adjustable comes from combining the verb adjust with the suffix -able to mean capable of being adjusted. It entered English as a straightforward formation based on its root meaning.