The Collaborative International Dictionary of English v.0.48:
Masquerade \Mas`quer*ade"\, v. i. [imp. & p. p. Masqueraded;
p. pr. & vb. n. Masquerading.]
1. To assemble in masks; to take part in a masquerade.
2. To frolic or disport in disquise; to make a pretentious
show of being what one is not.
A freak took an ass in the head, and he goes into
the woods, masquerading up and down in a lion's
The Free On-line Dictionary of Computing (18 March 2015):
1. "NAT" (Linux kernel name).
2. Hiding the names of internal e-mail client
and gateway machines from the outside world by rewriting the
"From" address and other headers as the message leaves the
This is good practise because external users do not need to
know about internal changes in message routing. The external
mail gateway needs to know how to route incoming replies back
to the original sender.