1 B2 idiomatic informal
To realise or become aware of something, especially something that was not immediately obvious.
"The teacher soon clocked onto the fact that the students were copying each other's work."
inseparable
clock onto
B2 informal inseparable transitive
To notice or realise something, often something that others were hiding or that was not immediately obvious.
In plain English
To suddenly understand or notice something that you did not see before.
What does "clock onto" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic informal
To notice a person's suspicious or noteworthy behaviour.
"The security guard clocked onto the shoplifter the moment he walked in."
inseparable
Usage tip
Distinctly British informal English. Common in everyday speech. Suggests a moment of realisation, sometimes implying that the speaker was slow to notice. Occasionally written without 'to' as 'clock on.'
Words that pair with "clock onto"
Natural word combinations native speakers use most often.
trick plan scheme truth secret idea
How to conjugate "clock onto"
The five tense forms you'll use most often.
Base
clock onto
I/you/we/they
3rd person
clocks onto
he/she/it
Past simple
clocked onto
yesterday
Past participle
clocked onto
have + pp
-ing form
clocking onto
continuous
Hear "clock onto" in the wild
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