(uncountable) The ability to do a task, performance, or execution; a set of functions that something is able or equipped to perform.

In good working order. / Useful; serving a purpose, fulfilling a function / Only for functional purposes, notably in architecture

What something does or is used for. / A professional or official position. / An official or social occasion. / Something which is dependent on or stems from another thing; a result or concomitant.

plural of function

Third-person singular simple present indicative form of function

present participle of function

Action of the verb function. / Manner by which something functions; the workings.

Functional, working / (euphemistic, of a person) Mentally disabled but still able to survive in wider society.

plural of functionality

simple past tense and past participle of function