Alternative spelling of on the air, especially when used attributively.

Speaking or acting for.

Accurate, or accurately predicted. / With accuracy. / (sports, of a shot) Towards the goal.

(Incoterm) without charge to the purchaser for delivery on board a carrier (originally a ship), at a specified location or point; used in such phrases as FOB destination to specify the point where the title of goods passes from the seller to the buyer

Punctually or according to the schedule. / By installments, payments over a period of time. / (chess) By a player's running out of time.

Punctual or according to schedule.

(idiomatic) To watch and pay attention to, in case of misbehaviour or mishap.

(transitive, idiomatic) To persist or continue. / (intransitive, idiomatic) To persist in talking about a subject to the annoyance of the listener.

On one's feet; walking, jogging or running but not in a vehicle or on the back of an animal. / (now rare, chiefly hunting) On the move; astir. / In progress or in preparation; active, in operation.

(UK, Australia, informal) functioning erratically, malfunctioning; not working or not working well. Usually refers to a mechanical or electrical device.