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MERCAPTAN

/məˈkapt(ə)n/9 letters

Definition of MERCAPTAN

noun

Any of a class of organic compounds of sulphur, ( R-SH ) where R represents an alkyl or other organic substituent. They tend to be foul-smelling. They are also termed thiols or thioalcohols.

Wiktionary · CC BY-SA

Where it comes from

Borrowed from German Mercaptan, from Danish mercaptan; coined by organic chemist William Christopher Zeise in 1832 from mer(curius) (“mercury”) + captan(s) (“capturing”), because the thiolate group bonds very strongly with mercury compounds.

Etymology via Wiktionary (CC BY-SA).

Rarity score
Withheld
Revealed only in play
Tier
Withheld
Find it yourself

OUTLIER scores every word on how unusual it is, and that number is not published. Working it out at the board is the game.

MERCAPTAN in OUTLIER

Players have found it on 7 boards so far.

Day 1Day 120
Its 7 boards, across 120 finished boards · taller bars are busier boards
7
Boards found on
27
First board
108
Latest board
48
Longest gap, days

It first turned up on Day 27, 16 June 2026. The most recent board was Day 108, 5 September 2026. Nobody has seen it on a board for 12 days.

First ever to find it

pico

on Day 27, 16 June 2026 - before anyone else in Outlier's history. See the Pioneers

Also on

Built from these letters

MERCAPTAN
9
Letters
3
Vowels
6
Consonants
8
Different letters
2
Longest consonant run
1
Longest vowel run

MERCAPTAN starts with M and ends with N. Sorted, its letters read AACEMNPRT - the shape to hunt for when the grid is scrambled. A appears more than once.

Words that start MERCAP

Its neighbours in the OUTLIER dictionary - shortest first.

MERCAPTOMERCAPTANSMERCAPTIDEMERCAPTIDESMERCAPTOPURINEMERCAPTOPURINES

Could you have found MERCAPTAN?

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.

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The OUTLIER card for MERCAPTANDownload image