From QWiki

Binds usually mean team binds. Team binds allow you to report strategic information in a team game, such as your current position, combat status, the situation of vital keys on a map, etc.

Other binds also exist, such as taunt binds, which are pre-fabricated taunts or wise sayings that you can "type" at the press of a key. It all started with Thresh's "Nice shot, Jimbo!", or did it?

Clan Earthquake released a popular team bind config called eq240 and flintheart created a lot of modern Loc files files (learning from many loc masters before him) that are a key component of team binds. (Originally locs needed a proxy to work, but now they are an integral part of the QW client)

QuakeWorld terminology
Game stuff
Quad | Ring/Eyes | Pent
GA | YA | RA | Mega
Axe | SG/Boomstick | SSG | NG | SNG | GL | RL | LG/Shaft
Binds | Bunnyhop | CFG | Demo | Duel | FFA | Frag | Rocket Jump | GLRJ | rpickup | pickup
Cam | Flood | +forward | BG | CS | GG | HPW | LPB | MGT | MST | Kenya | Rapecloset | TB3 | Stomp | BO3 | BO5 | Div1 delay | kpickup