Dissipation means the gradual dispersal or wasting away of something, like energy, resources, or even feelings. When you blow on a dandelion and watch the seeds scatter in all directions until they disappear, you're watching dissipation in action.

In science, dissipation describes how concentrated energy spreads out and becomes less useful. When you rub your hands together, the motion creates heat that quickly dissipates into the surrounding air. A cup of hot chocolate left on the counter gradually loses its warmth through dissipation. The energy doesn't vanish, but it spreads out so much that it becomes difficult to gather back together.

The word also describes wasting resources foolishly. If someone receives birthday money and immediately spends it all on candy and cheap toys, that's dissipation of their funds. A student who dissipates their study time by constantly getting distracted isn't using their energy wisely.

You might also encounter the word describing how strong emotions or tension fade away. After a tense moment in class, the nervous feeling slowly dissipates as everyone relaxes. The related verb dissipate means to scatter or fade in this way: fog dissipates when the sun comes out, and your worries might dissipate after talking with a friend.