Words Ending With SIS

100 words

Words ending in -SIS form one of English's most recognizable scientific and medical word families. This Greek suffix meaning 'process' or 'condition' gives us terminology for everything from cellular division to disease states, making these words essential for medical professionals and word game enthusiasts alike.

3-letter words

1

5-letter words

2

6-letter words

7

7-letter words

10

8-letter words

19

9-letter words

15

10-letter words

11

11-letter words

9

12-letter words

8

13-letter words

10

14-letter words

4

15-letter words

3

16-letter words

1

Pattern Guide

Insights and recommendations for these words.

The -SIS ending creates some of the most satisfying long words in competitive word games, combining high letter counts with unexpected playability.

Vocabulary & Language

Linguistic patterns and usage statistics

The suffix -SIS derives from Ancient Greek, where it indicated an action, process, or condition. In English, it predominantly forms nouns describing biological processes (mitosis, osmosis), medical conditions (psoriasis, neurosis), or states of being (crisis, basis). The suffix pairs reliably with Greek roots, which explains why -SIS words often sound technical—they were designed for scientific precision.

Total Words

639

0.2% of dictionary

Avg Length

10.5 letters

4.4 syllables

Top Scrabble

ZYGAPOPHYSIS

35 points

Longest Word

LYMPHOGRANULOMATOSIS

20 letters

Parts of Speech

Nouns
100%

This pattern is exclusively nouns—100% of words ending in -SIS function as nouns, with zero verbs, adjectives, or adverbs. The average word stretches to 10.5 letters with 4.4 syllables, reflecting the pattern's scientific vocabulary heritage where precision demanded longer, more specific terms.

Ancient Greek dominates this pattern overwhelmingly, reflecting the suffix's origins in scientific and philosophical Greek terminology. Many words traveled through New Latin and Late Latin before reaching English, as scholars coined medical and scientific terms by combining Greek elements with Latinate conventions. The etymology chain of HYPOTHESIS perfectly illustrates this journey: from Ancient Greek ὑπόθεσις through Latin and into Middle French before arriving in English.

Word Games

High-value words for board games

Short (2-4)

SIS

a female person who has the same parents as another person

3 pts

Medium (5-7)

ZYMOSIS

a process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol

21 pts
ZYGOSIS
20 pts
AUXESIS

growth from increase in cell size without cell division

14 pts

Long (8+)

ZYGAPOPHYSIS
35 pts
COCCIDIOIDOMYCOSIS

an infection of the lungs and skin characterized by excessive sputum and nodules

33 pts
LYMPHOGRANULOMATOSIS
33 pts
ADENOHYPOPHYSIS

the anterior lobe of the pituitary body; primarily glandular in nature

32 pts

Both Scrabble and WWF feature ZYMOSIS at 21 points as a top medium-length scorer. The real strategic difference emerges with longer words: LYMPHOGRANULOMATOSIS scores 33 points in Scrabble but jumps to 39 in WWF due to different letter valuations. For more accessible plays, AUXESIS offers solid points (14 in Scrabble, 15 in WWF) using common tiles. The Z-heavy options like ZYGOSIS provide reliable high scores across both games.

Wordle

5-letter words for daily puzzles

Good Starters (E, A, R, S, T)

ARSISStarter

Common Words (likely answers)

BASISCommon

the most important or necessary part of something

OASISCommon

a shelter serving as a place of safety or sanctuary

LYSISCommon

(biochemistry) dissolution or destruction of cells such as blood cells or bacteria

ARSISCommon

ARSIS makes a solid Wordle starter, testing the common consonants R and S while checking two vowel positions. Its five letters efficiently probe letter frequencies that appear across many -SIS words.

Length Extremes

Longest and shortest valid words

Longest

LYMPHOGRANULOMATOSIS20 letters
MICROELECTROPHORESIS20 letters
COCCIDIOIDOMYCOSIS18 letters
NEUROFIBROMATOSIS17 letters

Shortest

SIS3 letters

The lone short word SIS (3 letters) stands as an informal outlier in a pattern dominated by medical and scientific terminology. The Greek combining tradition naturally produces lengthy compounds, with LYMPHOGRANULOMATOSIS stretching to 20 letters.

Hidden Gems

Rare but valid words to surprise opponents

AMANUENSIS

someone skilled in the transcription of speech (especially dictation)

BRUCELLOSIS

an infectious disease of domestic animals often resulting in spontaneous abortion; transmittable to human beings

CANDIDIASIS

an infection caused by fungi of the genus Monilia or Candida (especially Candida albicans)

ECDYSIS

periodic shedding of the cuticle in arthropods or the outer skin in reptiles

ECDYSIS describes the periodic shedding of outer skin in reptiles or the cuticle in arthropods—essentially, the scientific term for when snakes shed their skin. Beyond its biological precision, this seven-letter word uses common tiles and offers word game players an unexpected valid play when opponents might challenge it.

Popular crossword answers

Words frequently used in crossword puzzles with common clues.