hard valve
Electronics (now chiefly historical )
noun
A thermionic valve or tube with a hard vacuum, or evacuated sufficiently for any remaining gas not to affect its performance.
Origin
Early 20th century; earliest use found in Wireless World.
- money advice
- money affairs
- money-back
- money bag
- moneybags
- money bank
- money belt
- money-bound
- money box
- money broker
- money-broking
- money bush
- money capital
- money-catching
- money center
- money-center bank
- money centre
- money-centre bank
- money changer
- money chest
- money claim
- money clause
- money clip
- money coffer
- money coiner