I define a minimal anagram as two words that are the same except that two adjacent letters are swapped. There are many examples: altitude/latitude, ample/maple, casual/causal, martial/marital, option/potion, perfect/prefect, quiet/quite, rogue/rouge, silver/sliver, and many others. What’s the longest minimal anagram?
Three kinds that I’m not interested in:
Word pairs that share a prefix or suffix. If both words have the same prefix or suffix and they can be removed and still make a minimal anagram, we’ll ignore those -fixes for the purpose of this question.
Spelling variants of the same word: theater/theatre.
Words that share the same base word and only twiddle the last letters: anthologies/anthologise.
So far the longest I’ve been able to find is 9 letters: complaint/compliant, optometer/potometer.