Definitions by Historical Accuracy

Chalk the bowl 

After taking a dump (likely large in nature), and flushing the excrement, if marks are left on the toilet bowl from your shit, you have successfully "chalked the bowl", and multiple flushes may be necessary to remove your prize or possibly a scrub of the toilet brush!

I like to chalk the bowl after a huge meal of Indian curry chicken.

Chalk the bowl by Historical Accuracy November 16, 2015