Boiler

How to spell boiler

6 letters · 2 syllables

How to pronounce boiler

Say the part in capitals loudest.

What does boiler mean?

1. nounA closed vessel or appliance that heats water to supply hot water and central heating, or to raise steam.

Boiler in a sentence

• The plumber serviced the boiler before winter set in.

• A new boiler cut their monthly energy bills considerably.

Where does boiler come from?

Language of origin: French

This word is built directly on the verb 'boil', which English took from Old French 'boillir' in the 1200s, itself descended from the Latin 'bullire' meaning 'to bubble' or 'to seethe'. That Latin verb grew from 'bulla', a word for a bubble or rounded swelling, the same root that gives us 'bull' in 'papal bull' (a sealed document) and even 'bullion'. The agent suffix '-er', a long-standing Germanic ending that turns a verb into the person or device that performs it, was added to give 'boiler', a noun for the apparatus that brings water to the boil. The sense of a self-contained vessel or appliance for heating water emerged with industrial steam technology in the 1700s and 1800s, and from there it settled into the modern household meaning of a unit that supplies hot water and central heating. Because the spelling simply joins the familiar 'boil' to '-er', the only real trap is remembering the 'oi' vowel pair rather than writing it as it sounds.

How the word is built

• boil (from Latin bullire, to bubble)
• -er (agent/instrument suffix, the thing that does the action)