After Mr. Roosevelt signed, Mr. Cummings observed that this measure "puts the capsheaf" on Mr. Roosevelt's long fight for court reform.

But this is the capsheaf of all his didoes.

And Lucas is certainly the capsheaf.

“What–what do I care if they shouldn’t leave me a pinch if only I could find something–even a few more rags of the parachute!” gasped Pemrose, in stifled tones of passion, as she climbed, hurry-skurry, over a piled capsheaf of bowlders.

Sammy was in evil repute in the neighborhood in any case; this was considered the capsheaf.