They started as same word, but their meanings have drifted apart over time.
A word that (literally) drives people nuts
Editor Emily Brewster clarifies the difference.
Why does it sound strange to say 'funner' or 'funnest?'
Or both? Or neither?
'Mischievous,' 'nuclear,' and other words to pronounce with caution.
An old-fashioned rule we can no longer put up with.