To augment something means to make it larger, greater, or stronger by adding to it. When a baker augments a cake recipe with extra chocolate chips, she's changing it by adding more of something good. When a football team augments its defense by recruiting talented new players, they're strengthening what they already have.

The word suggests change through addition rather than complete replacement. A musician might augment her piano skills by learning guitar, adding to her abilities without giving up what she already knows. A scientist might augment experimental data by running additional tests, building on existing findings to get a fuller picture.

In everyday life, students might augment their allowance by doing extra chores for neighbors, or augment their arguments in an essay by including more evidence. The key idea is enhancement: you're taking something that already exists and making it more substantial, more powerful, or more complete by adding to it.