on the knocker イディオム
Black as Newgate's knocker
(UK) If things are as black as Newgate's knocker, they are very bad. Newgate was an infamous prison in England, so its door knocker meant trouble.
on the knocker
Going aperture to door, as to accost a sale, a vote, or information. Primarily heard in UK, Australia. When I was aloof out of college, I had a job on the knocker for a adaptable buzz provider to get bodies to about-face their plans. We're advancement anybody who wants to see this election canyon to get out on the knocker and advance the word.Learn more: knocker, onon the knocker
1 activity from aperture to door, usually canvassing, buying, or selling. 2 (of payment) immediately; on demand. Australian & New Zealand informalLearn more: knocker, on