stop, cease, notches where drawstring is attached to the bow
弭 centers on bringing something to a halt: stopping, ceasing, or the physical notches on a bow where the string is attached and the drawing motion ends.
弭 combines 弓 (bow) with 耳 (ear), which likely served as a phonetic component. The meaning of stopping or ceasing may be an extension from the bow notches where the string rests, or the character may have been borrowed for its sound.
Picture a bow (弓) with an ear (耳) attached to it. The ear listens for the command to stop shooting, so the bow ceases its action at the notches where the string is drawn.
For ビ, imagine a bee (ビ) landing on the bow's ear, and the archer stops drawing the string so the bee won't be disturbed: bee -> ビ.