Heft means weight or heaviness that you can feel when you lift or hold something. When you pick up a thick dictionary or a watermelon at the grocery store, you feel its heft in your hands. The word captures that solid, substantial feeling of an object that has real mass to it.

You might heft something by lifting it up and down slightly to judge how heavy it is. A baseball player hefts different bats before choosing one, feeling which weight suits them best. A baker might heft a bag of flour to see if it's full or nearly empty.

The word often suggests both physical weight and importance or substance. Something with heft feels solid, serious, and well-made. A book with real heft might be physically heavy and also packed with important ideas. When people talk about an argument or proposal having heft, they mean it carries real substance and influence, backed by solid reasoning and evidence.

As a verb, heft means to lift something heavy. You might heft your backpack onto your shoulders on Monday morning, feeling the weight of all those textbooks. Heft captures both the physical act of lifting and the sense of dealing with something substantial.