1 C1 neutral
To identify or classify a specimen or species using a dichotomous or identification key.
"The students used the field guide to key out the plant they had collected from the riverbank."
separable
key out
C1 neutral separable transitive
To identify or classify something using a key or system; in video/photo editing, to remove a specific colour or background.
In plain English
To use a system to name or sort something, or to cut out the background colour in a video.
What does "key out" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 idiomatic neutral
In video or photo editing, to remove a specific colour (usually green or blue) from footage to replace it with another image.
"She keyed out the green background and replaced it with footage of a tropical beach."
separable
Literal vs figurative
Words literally mean
To use a key to get something out.
Actually means
To use a system to name or sort something, or to cut out the background colour in a video.
Usage tip
Used in biology/botany when identifying species using a dichotomous key. Also common in video production and broadcasting to describe the chroma-keying (green screen) process. Highly technical in both uses.
Words that pair with "key out"
Natural word combinations native speakers use most often.
background colour species sample green screen channel
How to conjugate "key out"
The five tense forms you'll use most often.
Base
key out
I/you/we/they
3rd person
keys out
he/she/it
Past simple
keyed out
yesterday
Past participle
keyed out
have + pp
-ing form
keying out
continuous
Hear "key out" in the wild
Listen to native speakers using "key out" in real YouTube videos — click a clip to watch it on Looplines.
Other ways to say "key out"
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