PIE *bendh- "to bind" (cf. Goth bandi "that which binds; Skt. bandhah "a tying, bandage," source of bandana; M.Ir. bainna "bracelet"). Most of the fig. senses of this word have passed into bond
(q.v.), which originally was a phonetic variant of band. The meaning "a flat strip" (late 14c.) is from O.Fr. bande "strip, edge, side," via O.N.Fr. bende, from O.H.G. binda, from P.Gmc. *bindan (see above). In M.E., this was distinguished by the spelling bande, but since the loss of the final -e the words have fully merged. Meaning "broad stripe of color" is from 1470; the electronics sense of "range of frequencies or wavelengths" is from 1922. The O.N.Fr. form was retained in heraldic bend.
"an organized group," late 15c., from M.Fr. bande , traceable to P.Gmc. root of band
(1), probably via a band of cloth worn as a mark of identification by a group of soldiers or others (cf. Gothic bandwa "a sign"). The extension to "group of musicians" is c.1660, originally
musicians attached to a regiment of the army. To beat the band (1897) is to make enough noise to drown it out, hence to exceed everything.