Checks a file for spelling errors
aspell action [options] filename
The aspell utility checks words in a document against a standard dictionary. You can use the aspell utility interactively: It displays each misspelled word in context, together with a menu that gives you the choice of accepting the word as is, choosing one of aspell's suggested replacements for the word, inserting the word into your personal dictionary, and entering a new word. You can also use aspell so that it reads from standard input and writes to standard output. This mode is suitable when you want to redirect standard input or output or simply want a list of misspelled words, one per line.
For more information refer to /usr/share/doc/aspell* on your system (with ...