When your bowling ball falls into the gutter, but still manages to get a spare. Usually when only one of the 7 or 10 pins are left standing from the previous frame.
I got 9 pins on the first ball, then I threw a gutter spare.

Person A: Did you see that? The ball rocked so far in the gutter that it clipped the 7 pin and I got a spare.
Person B: Yeah, dude! Nice gutter spare!
by Overregularizer October 15, 2021
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In bowling: when the ball goes into the gutter on the first roll of the frame, but then knocks down all pins on the second try.
Your strikes are backward! You’ll never improve your score if you keep throwing gutter spares back to back!
by AXEWAVE_ April 30, 2022
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