valveless
Lacking flow control
Valveless means lacking valves—mechanical devices that control flow.
A valveless pump moves fluid through other means, such as oscillation.
Valveless brass instruments like the bugle produce notes only through the player's embouchure, unlike trumpets with their valve systems.
The simple valveless design requires less maintenance.
Valveless military horn
- conchSpiral-shelled marine gastropod
- didgeridooAustralian Aboriginal wind instrument
- alphornSwiss mountain signaling horn
- natural trumpetValveless brass instrument
natural horn · shofar · vuvuzela · serpent · post horn · cornett · panpipes · ocarina
Having no barriers
- streamlinedMade smooth and efficient
- free-flowingMoving without restriction
- unrestrictedHaving no limitations
- siphonLiquid transfer tube
unidirectional · laminar · continuous · smooth · unimpeded · direct · bypass
Reciprocating cylinder component
Of certain blood vessels
- lymphaticOf fluid-draining vessels
- incompetentLacking necessary skill
- refluxBackward liquid movement
- varicoseAbnormally enlarged, twisted
bugle
Valveless military horn
- conchSpiral-shelled marine gastropod
- didgeridooAustralian Aboriginal wind instrument
- alphornSwiss mountain signaling horn
natural trumpet · natural horn · shofar · vuvuzela · serpent · post horn · cornett · panpipes · ocarina · recorder
unobstructed
Having no barriers
- streamlinedMade smooth and efficient
- free-flowingMoving without restriction
- unrestrictedHaving no limitations
siphon · unidirectional · laminar · continuous · smooth · unimpeded · direct · bypass
piston
Reciprocating cylinder component
sleeved · two-stroke · rotary · pulse-jet
venous
Of certain blood vessels
- lymphaticOf fluid-draining vessels
- incompetentLacking necessary skill
- refluxBackward liquid movement
varicose · insufficiency · backflow · regurgitation · prolapse