Initial

Part of speech: noun (n.)

The first letter of a word or a name.

Part of speech: verb (v.)

To put an initial to; to mark with an initial of initials. [R.]

Part of speech: adjective (a.)

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.