Rimes and phonemes are terms used in studying and teaching phonemic awareness. Phonemic awareness deals only with the auditory portion of preparing emerging readers, it does not involve print in the way Phonics does.
“The onset is the part of the word before the vowel; not all words have onsets. The rime is the part of the word including the vowel and what follows it.” A rime is the part of a syllable which consists of its vowel and any consonant sounds that come after it. Syllables can be divided into onsets and rimes. For example, in the word drop, the sound made by /dr is the onset, while the sound made by /op is the rime.
Phonemes are the smallest units of speech. Although there are 26 letters in the English language, there are close to 40 phonemes, or sound units. Each phoneme has an associated sound but rarely do they have a specific meaning. The word drop has three phonemes: dr/o/p.