Become less in amount or intensity

Usage examples of slacking.

It was not the five-bladed slave whip, invented for the full and perfect punishment of an erring slave girl, but only a light, one-bladed bosk whip, little more than a switch of leather, a mere incitement and encouragement to better performance on the part of a slacking plow beast, but it struck my back like a hot snake and a rifle shot.

Stubb benevolently towed away at his whale the other way, ostentatiously slacking out a most unusually long tow-line.

It did not matter that Bearden, by slacking off --whether consciously or because she was dissipating her energy -- was surely destroying her own chances for a career in the field, while Wheeler's conscientiousness would surely pay handsome dividends in both a scientific and a professional sense.

At full tilt they hurtled into the outreaches of the forest, leaping a fallen branch, dodging sudden trees, not slacking pace at all, until at last Dave became aware that the wolves were no longer chasing them.

He was a strong, healthy young man, with a sex drive that had shown no signs of slacking off since his middle teens.