The story
From the resemblance of the glass cap to the cup of an acorn.
Etymology from Wiktionary, CC BY-SA 4.0.
acorn tube
Today it means: A kind of vacuum tube with a glass cap at one end. Full definition →
Today it means: A kind of vacuum tube with a glass cap at one end. Full definition →
From the resemblance of the glass cap to the cup of an acorn.
Etymology from Wiktionary, CC BY-SA 4.0.