From Longman Dictionary of Contemporary Englishchock-a-blockchock-a-block /ˌtʃɒk ə ˈblɒk◂ $ ˈtʃɑːk ə ˌblɑːk/ adjective [not before noun] British English FULLcompletely full of people or thingschock-a-block with Paris was chock-a-block with tourists.
Examples from the Corpus
chock-a-block• At six in the morning the tradesmen's entrance had been chock-a-block with fishermen, and the kitchen resembled Billingsgate.• Best of all were the three libraries, which were chock-a-block with rare and ancient books.Origin chock-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 