chock-a-block• At six in the morning the tradesmen's entrance had been chock-a-block with fishermen, and the kitchenresembled Billingsgate.• Best of all were the three libraries, which were chock-a-block with rare and ancient books.
Originchock-a-block
(1800-1900)chock-a-block“with the wooden blocks of a tackle (= ropes for lifting) touching each other, so that no more can be lifted”((1800-1900)), from chock on block; influenced by chock-full