2. Designating the first letter or letters of a word. n. 1. a. The first letter of a proper name. b. initials The first letter of each word of a person's full name considered as a unit: stationery monogrammed with her initials. 2. The first letter of a word. 3. A large, often highly decorated letter set at the beginning of a chapter, verse, or paragraph.
Rhyme was most often used in these songs because people could remember rhyming songs better than non-rhyming ones, so rhyming songs endured while non-rhyming ones were quickly forgotten.
1 eye rhyme: This refers to rhymes based on similarity of spelling rather than sound. Often these are highly conventional, and reflect historical changes in pronunciation: love/move/prove, why/envy.  identical rhyme: A word rhymes with itself, as in Emily Dickinson's Because I Could not Stop for Death: