Whip pan

Whip the camera hard left or right and the frame turns to blur for 4 or 5 frames. Cut from the blur at the end of one shot into a matching blur at the start of the next, and the two read as one continuous move.

The match is the whole thing. Same direction, similar speed, similar amount of blur. Mismatch any of those and it reads as a mistake with a swoosh on top. Editors fake it in post by adding directional blur to a cut where the shots were filmed flat.