1 C1 formal
To be officially discharged from military service at the end of one's term or duty.
"After completing his four-year contract, he was mastered out with full honors."
inseparable
master out
C1 formal inseparable intransitive
To be formally discharged or released from military service.
In plain English
Leave the army or military because your time is done and you are officially let go.
What does "master out" mean?
One main meaning — here's how to use it.
Usage tip
This is a relatively rare and somewhat non-standard variant of 'muster out.' Primarily encountered in American military contexts. Some speakers use it interchangeably with 'muster out,' though 'muster out' is more widely recognized. Usage is highly specialized.
Words that pair with "master out"
Natural word combinations native speakers use most often.
military service army honorably forces corps
How to conjugate "master out"
The five tense forms you'll use most often.
Base
master out
I/you/we/they
3rd person
masters out
he/she/it
Past simple
mastered out
yesterday
Past participle
mastered out
have + pp
-ing form
mastering out
continuous
Hear "master out" in the wild
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Other ways to say "master out"
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