Science, Tech, Math › Science Definition of Weight Share Flipboard Email Print Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate by Todd Helmenstine Updated March 08, 2017 Definition: Weight is the name of the force exerted on an object due to the acceleration of gravity. The weight is equal to the mass times the acceleration due to gravity (9.8 m/sec2 on Earth). Common Misspellings: wieght Continue Reading