initial

adj

1. (not-comparable)Chronologically first, early; of or pertaining to the beginning, cause or origin.

   “Our initial admiration for their efficiency gave way to disgust about their methods.”

   “The initial stages of a syndrome may differ vastly from the final symptoms.”

   “Meanwhile Nanny Broome was recovering from her initial panic and seemed anxious to make up for any kudos she might have lost, by exerting her personality to the utmost. She took the policeman's helmet and placed it on a chair, and unfolded his tunic to shake it and fold it up again for him.”

   “While the first part to Manchester is level after the initial climb out of Liverpool, the section over the Pennines between Manchester and Leeds is very difficult, with steep gradients as well as many slowings over junctions and curves.”

2. (not-comparable)Spatially first, placed at the beginning, in the first position; especially said of the first letter of a word.

   “The initial letter of names is usually printed with a capital letter.”

   “Thus, when he drew up instructions in lawyer language, he expressed the important words by an initial, a medial, or a final consonant, and made scratches for all the words between; his clerks, however, understood him very well.”

noun

1. The first letter of a word or a name, especially of a person's full name (their initials).

   “The point of interest about this particular specimen was that it must have remained intact for at least a quarter of a century, as it had embossed in the frosted glass the initials of the old Great North of Scotland Railway in the form of a scroll, the sort of relic of pre-grouping days that can still be found here and there if one is observant.”

2. A distinguished initial letter of a chapter or section of a document.
3. onset, part of a syllable that precedes the syllable nucleus in phonetics and phonology.

verb

1. (transitive)To sign one's initial(s), as an abbreviated signature.

   “Please initial each page and sign the contract in full at the bottom.”