The rare daily word game sweeping the globe. Find what's hidden in plain sight.
PTERIN
Definition of PTERIN
noun
A ketonic amide derivative of pteridine responsible for some of the colouring in nature. It is also a component of folic acid.
Wiktionary · CC BY-SA
Where it comes from
From Greek: πτερόν (pteron) = wing (because it was first found in butterfly wings).
Etymology via Wiktionary (CC BY-SA).
Word DNA
How it is built
Same root, PTERIN · 1 relative in the game
OUTLIER scores every word on how unusual it is, and that number is not published. Working it out at the board is the game.
PTERIN in OUTLIER
Players have found it on 17 boards so far. 15 players have found it across Outlier's history.
It first turned up on Day 48, 7 July 2026. The most recent board was Day 147, 14 October 2026. Nobody has seen it on a board for 4 days.
First ever to find it
on Day 48, 7 July 2026 - before anyone else in Outlier's history. See the Pioneers
Built from these letters
PTERIN starts with P and ends with N. Sorted, its letters read EINPRT - the shape to hunt for when the grid is scrambled. No letter is used twice, which makes it an isogram.
Same letters, different word
2 other words use exactly these letters. Worth knowing at the board: an anagram fits a grid the same way.
Also seen on Day 48
Could you have found PTERIN?
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 48 - and most players walked straight past it.
Play today's OUTLIER