Two words are rhymes if they are stressed on the same syllable, counting from the end of the words, and are pronounced identically from the vowel in their stressed syllable to the end, but differ in sound immediately before that vowel.
Wiktionary follows this strict definition of a rhyme. For example:
కుక్క(kukka), మొక్క(mokka) and చిన్నక్క(cinnakka) are all rhymes, because they are all stressed on the final syllable and are pronounced identically from the vowel sound in that syllable to the end of the word.
undid and liquid are not rhymes, as they are stressed on different syllables (the final and penultimate syllables, respectively).