When using "coup" to refer to a governmenttakeover, you oftenaccompanyit with "d'état" to specify that it's a politicalevent.
When referring to a successfulaction, you can use "coup" onitsown.
Examples
PoliticalContext:
"The militarystaged a couplastnight, removing the president from power."
SuccessContext:
"Winning the championshipwas a realcoup for the team, especiallyafter their losing streak."
AdvancedUsage
In political discussions, you mighthearphraseslike "coupattempt" or"failedcoup," which refers to efforts to overthrow a government that did notsucceed.
In businessorpersonal achievements, you mighthear "a coup of marketinggenius" to describe a veryclevermarketingstrategy.
WordVariants
Coup d'état: This is the full term for a suddenoverthrow of a government.
Coup de grâce: This is a differenttermmeaning "a finalbloworshotgiven to kill a woundedperson." It is notrelated togovernmentbut is oftenconfused with "coup."
DifferentMeanings
Besides the political and success meanings, "coup" can sometimesrefer to anysuddenorsurprisingevent that bringsabout a significantchange, although this is lesscommon.
Synonyms
For the politicalmeaning:
Overthrow
Takeover
Insurrection (thoughthis has a slightlydifferentmeaning)
For the successmeaning:
Achievement
Triumph
Victory
Idioms and PhrasalVerbs
Thereare no specificidiomsorphrasalverbsdirectlyrelated to "coup," but you may encounterphraseslike "pull a coup" which informallymeans to achievesomethingimpressiveorsurprising.
Summary
"Coup" is a versatileword that can mean a suddenchange in governmentor a remarkablesuccess.
Noun
a brilliant and notablesuccess
a sudden and decisivechange of governmentillegallyorbyforce