Words ending in -sion, -tion, and -cion

These endings are part of many everyday English nouns, but people often have problems with their spelling. Here are some guidelines to help you choose the right one:

Words ending in -sion

Help with spelling > Endings and beginnings > Words ending in -sion, -tion, and -cion

  • If the ending is pronounced as in confusion, then it should be spelled -sion. Here are some examples:

collision

division

fusion

revision

confusion

erosion

incision

seclusion

decision

explosion

persuasion

vision

  • When the ending comes after an -l, it's always spelled -sion:

compulsion

emulsion

impulsion

repulsion

convulsion

expulsion

propulsion

revulsion

  • When the ending follows an -n or -r, it's often spelled -sion, especially if the word is related to one that ends in -d or -se. For example: immersion (from immerse) and comprehension (from comprehend). Here are some more examples:

apprehension

conversion

extension

pretension

aversion

diversion

perversion

version

  • Nouns based on words that end in -ss or -mit always end in -sion. For example: permission (from permit) and discussion (from discuss). Here are some more examples:

admission

depression

impression

submission

aggression

emission

intermission

succession

commission

expression

obsession

transmission

Words ending in -tion

  • If the ending is pronounced as in station, then it's spelled -tion. For example:

addition

duration

nation

solution

ambition

edition

notion

station

caution

emotion

position

vocation

  • If the noun is related to a word ending in -ate, then the ending will be -ation. For example: donation (from donate) or vacation (from vacate). Here are some more examples:

abbreviation

creation

location

rotation

accommodation

education

mediation

veneration

  • If the ending comes after any consonant apart from -l, -n, or -r, then the ending is spelled -tion:

action

connection

infection

reception

affection

deception

interruption

satisfaction

attraction

description

obstruction

suggestion

collection

exception

perception

transaction

  • After -n and -r, the ending can be -tion or -sion. It's more likely to be -tion if the word's related to another one that ends in -t or -tain. For example: assertion (from assert) or retention (from retain). Here are some more examples:

abortion

desertion

distortion

extortion

abstention

detention

exertion

invention

Words ending in -cion

There are just two common nouns that end in -cion: suspicion and coercion.


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