(electronics) An electron tube in which high-energy microwaves are produced by transferring energy from electrons

(medicine) A potentially fatal condition caused by a feeding regimen given through a tube that provides too little water and too much protein in the diet.

A baby who was conceived by in vitro fertilisation and then implanted in the uterus of the mother.

A device that produces X-rays by directing energetic electrons into a metal target.

a vacuum tube in which electrons from a heated cathode are focused and deflected onto a phosphorescent screen; used in television sets etc

Pectinaria australis - an annelid beach worm that forms a fragile tapered tube, about 50 mm long made of grains of sand.

(inorganic chemistry) An analytical technique in which a sample is heated in a sealed tube, volatile metals being removed by sublimation to a cooler part of the tube from where they can be removed and weighed

plural of test tube baby

(electronics) A vacuum tube that displays still or moving images (such as for a television), by controlling the direction of a cathode ray emitted towards the front of the tube. The front is coated by a layer of fluorescent material, so that it emits light when struck by the beam.

(idiomatic) A situation that cannot be recovered or reversed to its original state.