Basically this is a lie/excuse, it means that a married man or woman will be back late at night doing whatever he/she is doing, such as partying, having sex with another woman/man, doing drugs or just generally having fun with friends after work.

It is a classic example to go out without your wife/husband and have fun

Do not get confused with "its just code for sex", that is bullshit, if a person says that, make him/her look like an idiot.

It was made famous in the film 40 days and 40 nights
matts friend: hey my friend says that nicoles husband works late

matt: so

matts friend: hes working late...... like working a different girl every night
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An excuse scummy men use to their wives, which means "I'm f***ing the secretary after work."
"Honey, I have to work late tonight."
(he's so f***ing someone!)
by Marciexx April 27, 2008
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