adj
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.
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
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.
A distinguished initial letter of a chapter or section of a document.
onset, part of a syllable that precedes the syllable nucleus in phonetics and phonology.
verb
To sign one's initial(s), as an abbreviated signature.
Please initial each page and sign the contract in full at the bottom.