socks and knocks
n.pl.— «Readers should understand clearly that if the power industry prevails in its court challenges to the initiative, the huge amount of money expected to be spent primarily on reducing what the industry commonly calls “socks and knocks” might not get spent. (“Socks and knocks” is a word play on the symbols for sulfur dioxide and nitrogen oxides, SO2 and NOx, respectively.)» —“Cleaning Up With ‘Socks and Knocks’” by Bill Paul Motley Fool Apr. 21, 2005. (source: Double-Tongued Dictionary)
Further reading
What if, instead of being an inanimate object, a dictionary were alive? That’s the idea behind a lavishly illustrated new children’s book called The Dictionary Story (Bookshop|Amazon) by Oliver Jeffers and Sam Winston. This is part of a...
Astronauts returning from space say they experience what’s called the overview effect, a new understanding of the fragility of our planet and our need to reflect on what humans all share as a species. A book about the end of the universe...