1
: to a position on
We climbed onto the roof.
Turn left onto Fifth Avenue.
2
: in or into a state of awareness about
put me onto your methods
was onto something that should have been pursued further—Bosley Crowther
3
—used as a function word to indicate a set each element of which is the image of at least one element of another set
a function mapping the set S onto the set T

onto

2 of 2

adjective

: mapping elements in such a way that every element in one set is the image of at least one element in another set
a function that is one-to-one and onto

Examples of onto in a Sentence

Preposition We climbed onto the building's roof. The book fell onto the floor. The water spilled onto the floor. The cowboy leaped onto his horse. Transfer the data onto a disk. Turn left onto Third Street at the traffic light.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Preposition
For instance, identical stones thrown in a perfect circle onto the pond would create strong constructive interference when all the waves met in the middle of the circle. — Philipp Strasberg, Scientific American, 20 Oct. 2026 Last year, a Senatobia officer threatened a Black woman with a Taser, pulling her from her car and onto the ground and arresting her during a confrontation over an accessible parking space in the same Walmart lot where Kohen was shot. — Sophie Bates, Arkansas Online, 20 Oct. 2026 Police said a dark Chevrolet pickup drove onto a field during a youth soccer game and struck children and adults. — Maggie Vespa, NBC news, 19 Oct. 2026 Pan Yan The substance is integrated into a transparent, medium-sized insert designed to fit onto a garbage bin lid. — Maryna Holovnova, New Atlas, 19 Oct. 2026 See All Example Sentences for onto

Word History

First Known Use

Preposition

1581, in the meaning defined at sense 1

Adjective

1942, in the meaning defined above

Time Traveler
The first known use of onto was in 1581

Browse Nearby Words

Cite this Entry

“Onto.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onto. Accessed 23 Oct. 2026.

Kids Definition

onto

preposition
on·​to
ˌȯn-tə, 
ˌän-;
ˈȯn-tü, 
ˈän-
1
: to a position on or against
leaped onto the horse
climbed onto the roof
2
: in a state of knowing about or becoming aware of
I'm onto their little game
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