Also called head rhyme or initial rhyme, the repetition of the initial sounds (usually consonants) of stressed syllables in neighboring words or at short intervals within a line or passage, usually at word beginnings, as in "wild and woolly," or the line from Shelley's "The Cloud":
I bear light shade for the leaves when laid
Sidelight: Alliteration has a gratifying effect on the sound, gives a reinforcement to stresses, and can also serve as a subtle connection or emphasis of key words in the line, but alliterated words should not "call attention" to themselves by strained usage.
(See also Euphony, Modulation, Resonance)
(Compare Assonance, Consonance, Rhyme, Sigmatism)

This definition is in context to Poetry. See more contextual defintions for Alliteration.