One who is capable of adapting to differing situations.
He was an able adapter, and could easily adjust to the differences when the company changed ownership.
One who adapts a thing, e.g. a play.
The critic gave rave reviews to the adapter of the ancient play, who worked to give the text more relevance to the modern day.
A device or application used to achieve operative compatibility between devices that otherwise are incompatible.
He had an adapter that let him plug his phone into the car's cigarette lighter for power.