Initial

a.	1.
	1.	Of or pertaining to the beginning; marking the commencement; incipient; commencing; as, the initial symptoms of a disease.
	2.	Placed at the beginning; standing at the head, as of a list or series; as, the initial letters of a name.
n.	1.	The first letter of a word or a name.
v. t.	1.	To put an initial to; to mark with an initial of initials. [imp. & p. p. Initialed ; p. pr. & vb. n. Initialing.]

Noun	1.	initial - the first letter of a word (especially a person's name); "he refused to put the initials FRS after his name"
Verb	1.	initial - mark with one's initials
Adj.	1.	initial - occurring at the beginning; "took the initial step toward reconciliation"

INITIAL. Placed at the beginning. The initials of a man's name are the first letters of his Dame; as, G. W. for George Washington. When in a will the legatee is described by the initials of his name only, parol evidence may be given to prove his identity. 3 Ves. 148. And a signature made simply with initials is binding. 1 Denio, R. 471. But see Ersk. Inst. B. 3, t. 2, n. 8.

OK, abecedarian, aboriginal, accept, accredit, affirm, alpha, alphabet, alphabetize, amen, antecedent, antenatal, approve, authenticate, authorize, autochthonous, autograph, breaking-in, budding, capitalize, certify, character, commencing, confirm, cosign, countersign, creative, early, elemental, elementary, embryonic, endorse, fetal, first blush, first glance, first impression, first inning, first lap, first move, first round, first sight, first stage, first step, formative, foundational, fundamental, gambit, germinal, gestatory, give permission, give the go-ahead, give the imprimatur, give thumbs up, headmost, in embryo, in its infancy, in the bud, inaugural, inceptive, inchoate, inchoative, incipient, incunabular, infant, infantile, initiative, initiatory, inscribe, introductory, inventive, le premier pas, leading, letter, maiden, mark, monogram, nascent, natal, notarize, opening, opening move, parturient, pass, pass on, pass upon, permit, pioneer, postnatal, pregnant, prenatal, primal, primitive, primitiveness, primitivity, primogenial, procreative, ratify, rubber stamp, rudimental, rudimentary, sanction, say amen to, seal, second, sign, sign and seal, subscribe to, support, swear and affirm, swear to, transcribe, transliterate, undersign, underwrite, ur, validate, visa, vise, warming-up, warrant