acorn valve
now rare
noun
1A mechanical valve resembling an acorn.
2 Electronics = acorn tube.
Origin
1930s; earliest use found in U.S. Patents.
- under cover of
- undercrackers
- undercroft
- undercurrent
- undercut
- underdaks
- underdamp
- under debate
- underdetermination
- underdetermine
- underdeveloped
- underdevelopment
- underdog
- underdone
- underdrawing
- underdress
- underdungers
- undereducated
- underemphasis
- underemphasise
- underemphasize
- underemployed
- underemployment
- under-equipped
- underestimate