To board or mount (something), especially a vehicle.
Please get on the bus as quickly as possible.
To be successful.
I hear John has a new job. How's he getting on?
(with "with") To progress (with).
It's time to get on with improving quality.
To become late.
It was getting on for midnight before I went to bed.
To become old.
My parents are visibly getting on a bit these days.
To have a good relationship; to get along.
I wish you and I could learn to get on.
To commence (an action).
The dishes need washing, the floor needs vacuuming, the laundry needs folding. Get on it!
Expresses surprise or disbelief.