"ment" is a suffix sometimes used to convert a verb into a noun.
Examples:
establishment
atonement
bereavement
endearment
achievement
punishment
harassment
judgment
embellishment
enticement
inducement
nourishment
employment
management
environment
"ment" is a suffix sometimes used to convert a verb into a noun. Examples:accomplishmentaccompanimentachievementAdvertisementAgreementallotmentAppeasementassessmentatonementbasementbereavementcementcommitmentdeploymentdeportmentdevilmentdisbursementDisagreementelementembellishmentemploymentendearmentEnjoymentenlightenmentenrollmententertainmententicementenvironmentescarpmentestablishmentFulfillmentgarmentgovernmentharassmentimplementinducementinvestmentJudgmentmanagementmomentnourishmentparliamentpavementpaymentpunishmentStatementsupplementTemperamenttestamentTreatment
sediment
basementagreementexcitementapartmentencouragementcement
movement
Punishment, Amendment, Retirement
-ment
Words ending in tious:ambitiouscontentiousfacetiousfactiousfictitiousflirtatiousfractiouspretentiousscrumptioussuperstitious
awarenessbaldnessbusinesscarelessnessfearlessnessforgetfulnessforgivenessgoodnessgreatnesshappinesshelpfulnesshopelessnesskindnesslazinesslikenessneedinessquietnessrudenesssadnessstuffinessthoughtfulnessthoughtlessness
the ending of the word assignment is suffix
The suffix for replacement is -ment. -ment means a state of.
the suffix "ment" means the result of an action or the condition of
-idle isn't a suffix. There are words that end with -idle, like bridle, but it isn't a suffix.