wamerican-large binary package in Ubuntu Bionic amd64

 This package provides the file /usr/share/dict/american-english-large
 containing a list of English words with American spellings.
 This list can be used by spelling checkers, and by programs such
 as look(1).
 .
 This is a larger list than the one installed by wamerican; nothing
 prevents you installing both (and others) at the same time.
 .
 There are also -small and -huge version of this word list,
 and there are wbritish* and wcanadian* packages as well.

Source package