A blue aniline dye used as an indicator in agar for detection of lipase activity in bacteria.

present participle of blue-sky

simple past tense and past participle of blue-sky

A pigment made from barium copper tetrasilicate (“BaO·CuO·(SiO₂)₄”), used in ancient China.

A pigment made from barium copper tetrasilicate (“BaCuSi₄O₁₀”), an artificial blue pigment, used by ancient Chinese for over 2 millennia before dying out at the end of the Han dynasty; one of the few alternates to azurite in ancient times.

A pigment made from calcium copper tetrasilicate (“CaCuSi₄O₁₀”), the first artificial pigment, a blue, used by Egyptians for over 3 millennia, before dying out during the Roman Empire; one of the few alternates to lapis lazuli during ancient times.

Ice that is blue in colour, formed by compressed snow on a glacier having its air bubbles squeezed out.

A blue paste made from Prussian blue and some oily substance, used to verify the mating of components by rubbing a coated workpiece against the target surface to leave marks.

plural of blue shirt

An Alaska State Trooper. / A sailor who works on the flight deck of an aircraft carrier, securing aircraft to the deck. / (US, medicine) An emergency medical service worker; a paramedic.