An apartment; a flat.
"The manufacturing team replaced the old manual dies with new APT stamps to increase production speed."
Initialism of automation presses tooling.
"The apt was narrow but had everything I needed for my week-long stay in London."
Suitable; appropriate; fit or fitted; suited.
"The new shoes were a perfect fit, as they felt both comfortable and stylish on her feet."
In plain English: Apt means something is naturally suited for a particular purpose or likely to happen soon.
"That comment was very apt given the situation we just discussed."
Usage: Use apt to describe something that seems likely to happen, such as an error being apt to occur, rather than simply meaning suitable. While similar to proper, it often carries a nuance of natural fitness for the occasion.
Initialism of Alabama Public Television.
"The local news segment was broadcast by APT, standing for Alabama Public Television."
The word "apt" comes from the Old French apte and Latin aptus, meaning suitable or fitting. It likely entered English through a root related to fastening things together or reaching something.