In civil law, a case where two or more people disagree and one or more of the parties take the case to a court for resolution.
"The neighbor filed a lawsuit against the construction company after their new building blocked sunlight from his garden."
In plain English: A lawsuit is when someone takes another person to court because they think that person did something wrong and wants them to pay or change their behavior.
"The company had to pay damages after losing its lawsuit against the competitor for stealing trade secrets."
Usage: A lawsuit is any legal action filed in court by an individual or entity against another party over a dispute. Use this term specifically when referring to formal civil proceedings rather than informal arguments or criminal charges brought by the government.
The word lawsuit is a straightforward combination of the words law and suit that emerged to describe legal proceedings. It literally means an action taken under the authority of the law.