In terms of syllables, what does 'onset' refer to?

Onset refers to the initial consonant or consonants of a syllable, which is an important concept in phonology and literacy instruction. In the structure of a syllable, the onset serves as the starting sound, preceding the vowel sound known as the nucleus. For example, in the word "black," the onset is "bl," with "a" being the nucleus. Understanding onsets is crucial for phonemic awareness, helping students recognize sounds in words, decode new words, and improve their reading skills. This knowledge supports various literacy activities, such as blending and segmenting phonemes.