adj. Of or pertaining words or statements formed in thought and expressed inwardly but not, or not yet, uttered aloud.
adj. Of or pertaining to imperfectly articulated speech that is inaudible or barely audible; subtonic.
the GNU version of the Collaborative International Dictionary of English
adjective-and-noun. Same as subtonic.
Word Usage
"So once again, too, with such a textual effect in subvocal mind, a compelling line of descent sketches itself between Romantic visionary enterprise and"