on|to

on|to «ON too, AWN-; before consonants often ON tuh, AWN-», preposition.

1. on to; to a position on or upon: »

to throw a ball onto the roof, to get onto a horse, a boat driven onto the rocks.

2. Informal. familiar with; aware of; experienced in: »

It doesn't take long to get onto him and his alibis.

Usage onto, on to. When on is clearly an adverb and to a preposition, the two words should of course be separated: »

The rest of us drove on to the city.

When the two words make a definite preposition, they are usually written solid: »

The team trotted onto the floor. They looked out onto the park.