Mirror has three rs and its a 6 letter word. so it has the most percentage of R's. Is that what you mean?
polygyny
POSSESSIONLESSNESS
Knickknack or knickknacks.
cutest
The word "the" is probably the most used word in English.
The most common word in the English language is the word the.
word least because the opposite of most is least
The word with the most Xs is hexakosioihexekontahexaphobia, a word for the fear of the number 666; a noun as a word for a thing.
The second most common word is 'be'
The word with the most S's is "possessiveness."
The most exotic word would be 'exotic'.
Jesus is the most used word
The most commonly used word in English is the word 'the'.
the most used word was i think it was it.
The most common curse word is hell
The word that is used most is "and"