| noun | process or manner of functioning or operating “the power of its engine determines its operation” |
| verb | perform as expected when applied “The washing machine won't go unless it's plugged in” |
| verb | serve a purpose, role, or function “The tree stump serves as a table” |
| verb | perform duties attached to a particular office or place or function “His wife officiated as his private secretary” |
| adjective | performing or able to perform its regular function “a functioning flashlight” |
| operate | verb | perform as expected when applied |
| function | verb | perform as expected when applied |
| functioning | noun | process or manner of functioning or operating |
| operative | adjective | (of e.g. a machine) performing or capable of performing |
| operant | adjective | having influence or producing an effect |
| operation | noun | process or manner of functioning or operating |
| function | noun | what something is used for |
| officiation | noun | the performance of a religious or ceremonial or public duty |
| office | noun | (of a government or government official) holding an office means being in power |
| officiating | noun | the act of umpiring |
| functionary | noun | a worker who holds or is invested with an office |