The rare daily word game sweeping the globe. Find what's hidden in plain sight.
ISOTHERM
Definition of ISOTHERM
noun
A line on a graph or chart, such as a weather map, along which all the points have the same temperature.
Wiktionary · CC BY-SA
Where it comes from
From the French isotherme (“of equal temperature”, adjective), itself from Ancient Greek ἴσος (ísos, “equal”) + θέρμη (thérmē, “warmth”). By surface analysis, iso- + -therm.
Etymology via Wiktionary (CC BY-SA).
Word DNA
Line of descent
- Ancient Greek
- French
- English
2 recorded generations before English.
Deepest traced root
2nd
of 59 source languages in OUTLIER
12.6%
of traced words share this origin (3,770)
branch · 12.6% of traced words
How it is built
OUTLIER scores every word on how unusual it is, and that number is not published. Working it out at the board is the game.
ISOTHERM in OUTLIER
Players have found it on 33 boards so far. 42 players have found it across Outlier's history.
It first turned up on Day 27, 16 June 2026. The most recent board was Day 150, 17 October 2026. Nobody has seen it on a board for 1 day.
First ever to find it
on Day 27, 16 June 2026 - before anyone else in Outlier's history. See the Pioneers
Built from these letters
ISOTHERM starts with I and ends with M. Sorted, its letters read EHIMORST - the shape to hunt for when the grid is scrambled. No letter is used twice, which makes it an isogram.
Same letters, different word
One other word uses exactly these letters. Worth knowing at the board: an anagram fits a grid the same way.
Words that start ISOTHE
Its neighbours in the OUTLIER dictionary - shortest first.
Also seen on Day 27
Could you have found ISOTHERM?
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 27 - and most players walked straight past it.
Play today's OUTLIER