step out phrasal verb (see also step)
to leave your home or office for a short time Synonym : pop out British English:
She’s just stepped out for a few minutes.

[TahlilGaran] Dictionary of Contemporary English ▲

step out
to leave a place, esp. for a short time.
Mr. Taylor just stepped out of the office to get the mail.

[TahlilGaran] English Idioms Dictionary ▲

step out
v. phr.
1. To go out, particularly socially, as on a date.
Paul said to Sylvia, "You look so dressed up tonight
■ you must be stepping out, eh?"
2. To leave for a short period during the work day to go to the lavatory or to get a cup of coffee. (Frequently said by secretaries over the phone.)
"May I speak to Mr. Kotz?" Roy asked. "I'm sorry, sir. He just stepped out for a minute," the secretary answered.

[TahlilGaran] English Idioms Dictionary ▲