What’s The #’s Real Name?A hash has referred to stripes on military jackets since as early as 1910. But, in the 1980s, people started using hash to refer to the # symbol.
Origin of miner's lettuce
An Americanism dating back to 1915–20
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019