Modification of Nouns with -tion and -sion

Many English nouns end with the suffix variants -tion and -sion. They are both variants of the suffix -ion. In many cases, the suffix -ion is added directly to the root. This is the case with forms such as confession and reaction. However, many nouns modify the root in combination with the suffix.

The following forms all have modified roots:

add-addition

appear-apparition

apply-application

combine-combination

comprehend-comprehension

describe-description

divide-division

organize-organization

reduce-reduction

solve-solution

The word appear is quite different from apparition. In fact, the word appearance also exists, but the word apparition is used for an unexpected, remarkable appearance. In words such as addition and combination, the epenthentic vowel changes the syllable structure from VC.C to V.CV.