assonance
The repetition of similar or identical vowel sounds (though with different consonants), usually in literature or poetry.
countable, uncountable
"You should try to speak without assonances" said Merlyn. "For instance, 'The beer is never clear round here, dear' is unfortunate, even as an assonance.'"
Where it comes from
From French assonance, from Latin assonāre; by surface analysis, a- + son- + -ance.
Adapted from the Wiktionary entry assonance (CC BY-SA 4.0).