·noun One who boils.
II. Boiler ·noun A vessel in which any thing is boiled.
III. Boiler ·add. ·noun A sunken reef; ·esp., a coral reef on which the sea breaks heavily.
IV. Boiler ·noun A strong metallic vessel, usually of wrought iron plates riveted together, or a composite structure variously formed, in which steam is generated for driving engines, or for heating, cooking, or other purposes.