'Transmit' is Latin for 'send across' — from 'trans-' + 'mittere.' Sibling of 'admit' and 'submit.'
To send or convey from one person, place, or thing to another; to pass on or communicate; to broadcast a signal.
From Latin 'trānsmittere,' meaning 'to send across, to transfer, to let pass through,' composed of 'trāns-' (across, beyond) and 'mittere' (to send, to let go). The literal image is of sending something across a boundary or distance. The broadcasting sense developed in the late 19th century with the invention of radio telegraphy. Like 'admit,' 'commit,' 'permit,' and 'dismiss,' this word descends from the prolific Latin verb
The first transatlantic radio transmission was sent by Guglielmo Marconi on December 12, 1901, from Cornwall, England, to Newfoundland, Canada. The entire message was the Morse code for the letter 'S' — three dots. That single letter, 'sent across' the Atlantic, proved that radio waves could follow the curvature of the Earth.