back to back
as one, as one man, at opposite extremes, behind, behind the scenes, coactively, coefficiently, collectively, combinedly, communally, concertedly, concordantly, concurrently, conjointly, contrariwise, contrary, cooperatingly, cooperatively, counter, eyeball to eyeball, face to face, hand in glove, hand in hand, harmoniously, in back of, in chorus, in concert with, in the background, in the rear, in unison, jointly, just opposite, nose to nose, opposite, poles apart, shoulder to shoulder, tandem, together, unanimously, vis-a-vis, with one voice
back to back
rear, back, posteriority, rear rank, rear guard, background, hinterland, occiput, nape, chine, heels, tail, rump, croup, buttock, posteriors, backside scut, breech, dorsum, loin, dorsal region, lumbar region, hind quarters, aitchbone, natch, natch bone, stern, poop, afterpart, heelpiece, crupper, wake, train, reverse, other side of the shield, back, rear, hind, hinder, hindmost, hindermost, postern, posterior, dorsal, after, caudal, lumbar, mizzen, tergal, behind, in the rear, in the background, behind one's back, at the heels of, at the tail of, at the back of, back to back
, after, aft, abaft, astern, sternmost, aback, rearward, ogni medaglia ha il suo rovescio, the other side of the coin.