onto

on·to  (nt, -t, ôn-)

prep.

1. On top of; to a position on; upon: The dog jumped onto the chair. See Usage Note at on.

2. Informal Fully aware of; informed about: The police are onto the robbers' plans.

adj. Mathematics

Of, relating to, or being a mapping such that every element of the target set referred to is the image of an element in the domain.

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onto or on to

prep

1. to a position that is on: step onto the train

2. having discovered or become aware of: the police are onto us

3. into contact with: get onto the factory

USAGE: Onto is now generally accepted as a word in its own right. On to is still used, however, where on is considered to be part of the verb: he moved on to a different town as contrasted with he jumped onto the stage.

Translations

onto [ˈɔntu] prep → su, sopra