首先來看一下維基百科上對該詞的定義：
Force majeure is a French term that literally means "greater force." It is related to the concept of an act of God, an event for which no party can be held accountable, such as a hurricane or a tornado. Force majeure also encompasses human actions, however, such as armed conflict. Generally speaking, for events to constitute force majeure, they must be unforeseeable, external to the parties of the contract, and unavoidable. These concepts are defined and applied differently depending on the jurisdiction.
（Force majeure是一個法語術語，字面意思是「超級力量」。它與act of God概念有關，一個任何一方都不能為之負責的事件，比如颶風或龍捲風。然而，不可抗力也包括人的行為，例如武裝衝突。一般來說，對於構成不可抗力的事件，它們必須是不可預見的，合同當事人之外的，並且不可避免的。這些概念的定義和應用因管轄權而異。）
[French) Irresistible compulsion or coercion. The phrase is used particularly in commercial contracts to describe events possibly affecting the contract and that are completely outside the parties' control. Such events are normally listed in full to ensure their enforceability; they may include *acts of God, fires, failure of suppliers or subcontractors to supply the supplier under the agreement, and strikes and other labour disputes that interfere with the supplier's performance of an agreement. An express clause would normally excuse both delay and a total failure to perform the agreement.
（[法語詞]不可抗拒的強迫或脅迫。該短語在商業合同中特別用來描述可能影響合同的、完全不在當事人控制範圍之內的事件。此類事件通常全部列出，以確保其可執行性；可能包括*天災（acts of God）、火災、供應商或分包商未能根據協議向供應商供貨，以及罷工和其他妨礙供應商履行協議的勞資糾紛。明示條款通常可以作為拖延和完全不履行協議的藉口。）
《原照英美法字典》對該詞的中文解釋為：（法）不可抗力 其字面含義為「超級力量」，作為法律用語，意旨不能預見、不能控制的事件或結果。但該詞的含義廣於英文中的「不可抗力」[acts of God]，因為他們不僅包括自然力，還包括認為的力量（例如暴亂、罷工、政府干預、戰爭行為等）。與本詞同義的另一法律法語是force majesture，但後者是一種不必要的同詞變體。
從上面的分析可以看出force majeure, act of God 和vis majeure三詞都可指不可抗力，只是act of God （英文）和vis majeure（拉丁語）僅指天災；force majeure（法語）不僅指天災，還指人禍。