The term varies by MFG. Audioquest calls it "Double Bi-wire." One connection at the amplifier end and two separate runs of cable to connect at two pairs of binding posts on the speaker end (you retain the full cable gauge at the speaker terminals.) Their "Single Bi-wire" is one connection at the amplifier end and one cable run that is split into two connections at the speaker end (you do not retain the full cable gauge at the speaker terminals.)
What is a "SHOTGUN" speaker cable??
What is the difference between, say, an Acoustic Zen Satori and the Acoustic Zen Satori Shotgun???