All phrasal verbs
on
/ɑn/27 verbsVowel-initial — links backwardsSomething starts running, keeps running, or sits on a surface.
ON is the opposite of OFF in the switching sense (turn on), but its bigger job is continuation: carry on, go on, hang on, keep on all mean do not stop.
A third sense is contact with a surface, which is why clothes go on — put on a coat, try on shoes.
What it does to the sound
In General American, ON has the /ɑ/ of father, not the rounded British /ɒ/. It is vowel-initial, so it links: hold on is “hol-don”, carry on gains a Y glide — “carry-yon”.
What ON means
Continuing — do not stop
The action persists past the point where it might have ended.
Every verb that takes ON
The complete list — 27 of them. The section above groups the common ones by what ON is doing.