initial

adj. placed at the beginning, first

v. sign using the first letter or letters of a name

n. beginning letter of a person's first name; first letter (as of a word); enlarged or ornamented letter at the beginning of a chapter

In a written work, an initial is a letter at the beginning of a work, a chapter or a paragraph that is larger than the rest of the text. The word comes from the Latin initialis, which means standing at the beginning. It is often several lines in height and in older books or manuscripts sometimes ornately decorated.
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Noun
1. the first letter of a word (especially a person's name); "he refused to put the initials FRS after his name"
(hypernym) letter, letter of the alphabet, alphabetic character
Verb
1. mark with one's initials
(hypernym) sign
(entail) approve, O.K., okay, sanction
Adjective
1. occurring at the beginning; "took the initial step toward reconciliation"
(similar) first

n. initial, beginning letter of a person's first name, first letter (as of a word)

adj. initial, inceptive, original