This town is chockablock with restaurants that are just clones of the same old themes.
-- Amy Tan, The Joy Luck Club
lf opossum and skunk and raccoon can hide there, survive there, year after year, decade after decade, almost in the middle of a teeming metropolitan chockablock, think how an enterprising monkey might fare.
-- Tom Robbins, Half Asleep in Frog Pajamas
Chockablock is of uncertain origin. It is likely related to the word chock-full which means "crammed". The word chock refers to a wooden block that holds something in place.