The rare daily word game sweeping the globe. Find what's hidden in plain sight.
HYPOCAUST
Definition of HYPOCAUST
noun
An underfloor space or flue through which heat from a furnace passes to heat the floor of a room or a bath.
Wiktionary · CC BY-SA
Other senses
HYPOCAUST carries 4 further meanings.
noun
A space under the floor of an ancient Roman building where heat from a furnace was accumulated to heat a room or a bath.
noun
In architecture, an arched fire-chamber, from which heat is distributed through earthenware pipes to the rooms above it. The term is also sometimes applied to a fireplace, furnace, or oven.
noun
A furnace, esp. one connected with a series of small chambers and flues of tiles or other masonry through which the heat of a fire was distributed to rooms above. This contrivance, first used in bath, was afterwards adopted in private houses.
noun
An underfloor heating system, even without such an underfloor space or flue, as adapted to the modern housing, east and west.
Where it comes from
From Latin hypocaustum, from Ancient Greek ὑπόκαυστον (hupókauston), from Ancient Greek ὑπό (hupó, “underneath”) + καυστόν (kaustón, “burnt offering”).
Etymology via Wiktionary (CC BY-SA).
Word DNA
Line of descent
- Ancient Greek
- Latin
- English
2 recorded generations before English.
Deepest traced root
3rd
of 59 source languages in OUTLIER
12.2%
of traced words share this origin (9,569)
branch · 12.2% of traced words
How it is built
Same root, HYPOCAUST · 1 relative in the game
HYPOCAUST in a sentence
“The stube, or stove, of a German inn, derived its name from the great hypocaust, which is always strongly heated to secure the warmth of the apartment in which it is placed.”
OUTLIER scores every word on how unusual it is, and that number is not published. Working it out at the board is the game.
HYPOCAUST in OUTLIER
Players have found it on 44 boards so far. 80 players have found it across Outlier's history.
It first turned up on Day 31, 20 June 2026. The most recent board was Day 157, 24 October 2026. Nobody has seen it on a board for 1 day.
First ever to find it
on Day 38, 27 June 2026 - before anyone else in Outlier's history. See the Pioneers
Built from these letters
HYPOCAUST starts with H and ends with T. Sorted, its letters read ACHOPSTUY - the shape to hunt for when the grid is scrambled. No letter is used twice, which makes it an isogram.
Words that mean much the same
Near-synonyms of HYPOCAUST. Not interchangeable at the board - the grid decides that - but close in meaning.
Words that start HYPOCA
Its neighbours in the OUTLIER dictionary - shortest first.
Also seen on Day 31
Could you have found HYPOCAUST?
OUTLIER is a daily word game. One grid, the same grid for everybody, and the words nobody else spots are the ones that pay. This word was on Day 31 - and most players walked straight past it.
Play today's OUTLIER