Having lower parts made of or covered by copper (especially of a ship or cookware). / (Britain, idiomatic) Thoroughly reliable; secure

Alternative spelling of copper sulfate

(chemistry) the common name for copper(II) sulfate, CuSO₄, which forms blue crystals and is used in agriculture, dyeing, electroplating and many other applications; reducing agents reduce it to the red cuprous sulfate

(obsolete) A hangover.

(geology) any rock containing commercially interesting amounts of copper

A person falsely giving themselves the title of captain.

(medicine) The cuprous salt of aspirin; it is used to treat rheumatoid arthritis

A tall type of beech, Fagus sylvatica atropurpurea, with smooth bark and reddish-brown to purple leaves.

A butterfly of the copper or gossamer-winged butterfly family, Lycaena virgaureae.

(dated) The mineral olivenite.