Mutants and mutineers are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It suggests what word you may want to save time, but quite often, its suggestions couldn’t be more off base and produces humorous results.
Mutants (pronounced “mew-tuhnts”) is a plural noun. It means a creatures that possess deviations from normal in their DNA (genes.) Mutants have been a familiar term in US pop culture thanks to the X-Men franchise. The X-Men possess supernatural abilities as opposed to the genetic mutations that happen to everyday human and animal lives.
Mutineers (pronounced “mew-tin-eers”) is a plural noun. It means sailors who revolt against their captain or superior officers on a boat, airship, or other vessel. It can also refer to any group staging a revolution or revolt in other settings.
The following story uses both words correctly:
Murvynn, a mutant with seven fingers on each hand, never guessed he could lead a charge of mutineers to overthrow a cruel, abusive captain on the way to the Americas in the early 1500s. They would throw the cruel captain overboard and left him for dead. Murvynn assumed his identity. In a new world, who would notice the change? And he was right, no one did for many years.