What is defination of equation? And why is it called a equation.​

An equation can be defined as a mathematical statement in which two expressions are set equal to each other. In simple words, equations mean equality i.e. the equal sign. Since equations are all about “equating one quantity with another”,they are simply known as equation

In algebra, an equation can be defined as a mathematical statement consisting of an equal symbol between two algebraic expressions that have the same value. ... For instance, 3x + 5 = 14 is an equation, in which 3x + 5 and 14 are two expressions separated by an 'equal' sign.