What term describes the close repetition of similar vowel sounds within different consonants?

The term that describes the close repetition of similar vowel sounds within different consonants is indeed assonance. Assonance is a literary device often used in poetry and prose to create rhythm and enhance the musical quality of the language. It occurs when vowels are repeated in close proximity, which can create a more melodic sound or unify a collection of words.

For example, in the phrase "The rain in Spain stays mainly in the plain," the repetition of the long "a" sound demonstrates assonance. This technique can evoke emotions and enhance the reader's experience by drawing attention to specific phrases or ideas.

In contrast, the other options represent different literary devices: alliteration involves the repetition of initial consonant sounds; hyperbole is an exaggerated statement not meant to be taken literally; and imagery refers to descriptive language that appeals to the senses. Each of these has its unique function in writing but does not specifically pertain to the repetition of vowel sounds as assonance does.