Question 1

What does "master out" mean?

Accepted Answer

To be officially discharged from military service at the end of one's term or duty.

Question 2

How do you use "master out" in a sentence?

Accepted Answer

After completing his four-year contract, he was mastered out with full honors.

Question 3

Is "master out" formal or informal?

Accepted Answer

"master out" is formal — used mainly in written or official contexts. 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.

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