What does "sb" stand for?

[Unregistered]

I ´d like to know what "sb" means in this sentence:

welcome: a friendly greeting to "sb" who has just arrived somewhere.

and what does this collocation mean: make sb laugh

my e-mail is: vytoryto369@hotmail.com

thanks for this space...

 

[Clare James]

sb means somebody.

In definitions text books and dictionaries often use the short forms -
something = sth
someone = so
somebody = sb