From Longman Dictionary of Contemporary Englishpunch out phrasal verb American English1 BECto record the time that you leave work, by putting a card into a special machine SYN clock out British English2 punch somebody outHIT to hit someone so hard that they become unconscious → punch→ See Verb table
Examples from the Corpus
punch out• I got so mad I just wanted to punch someone out.• The coach threw him off the team after he punched out a teammate.From Longman Business Dictionarypunch out to make a hole in a card as a record of the time when you left work, especially at a factory → punch→ See Verb table 