everybody
pron.every person in a group. You use this when you are talking about all the people in a specific place or the whole world.
pron.every person; all people in a particular group or in general. Functions as a singular pronoun and requires a singular verb form despite referring to multiple people.
“Everybody in the room is listening to the music.”
“Everybody at the office was invited to the party, so the building was completely empty by five o'clock.”
“While the policy was designed to benefit everybody, the administrative delays meant that only a fraction of the population received their payments on time.”
Always takes a singular verb (e.g., 'everybody is' not 'everybody are').
Despite referring to a group of people, 'everybody' is grammatically singular and requires a singular verb.
Usage everybody else
From every + body.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.