(entomology) A libellulid dragonfly, Agrionoptera insignis allogenes, a subspecies of the grenadier, of Australia, New Guinea, and the Solomon Islands.

(chemistry) Potassium ferricyanide, K₃[Fe(CN)₆], a highly poisonous ferric crystal salt of potassium cyanide used as a pigment. / The colour of this compound: a hue of semi-dark brownish red

Of a brownish hue of red colour.

(Australia, transport, obsolete) Any of various red coloured passenger trains formerly operating in eastern mainland Australia.

plural of red rattler

(UK politics) A set of constituencies, in the Midlands, Northern England and North East Wales, which have historically tended to support the Labour Party.

(simile) Bright red in color, especially from a bad sunburn.

(politics) Coordinated violence committed by communists, socialists, or other left-wing groups against (actual or perceived) class enemies.

(politics, history) Any one of several specific red terrors in history.

plural of red terror