English Translation
Sorry, I didn’t hear you.
How is this different from Entschuldigung?
It is a verb.
Ich entschuldige
Du entschuldigst
Er / … entschuldigt
Wir entschuldigen
Ihr entschuldigt
Sie entschuldigen
Yes, and in this case it’s also the plural imperative.
About short for “Entschuldigt mich bitte.” - “Please excuse me.”
Although I think this longer form would normally be interpreted as a request for an excuse to leave, which the short version does not imply.