People describe certain terms as a portmanteau of two other words, e.g. "fediverse is a portmanteau of federation and universe".
This of course assumes that everyone knows what "portmanteau" means.
Portmanteau is itself a portmanteau, combining port, from the Latin "portus" (harbour), and "manteau", a type of cloak.
In olden times, children of dockworkers would sneak into taverns by stacking themselves under one of these cloaks, pretending to be a tall adult.
