The doctor told me i have hyperthyroidism, what does that mean?

Over-active thryoid: Hyper means overactive. Hypo means underactive. Whe we, doctors say hyperthyroidism, we mean the thyroid galnd is putting out too much thyroid hormones. This can be caused by several reasons. Sometimes is transient, sometimes is not and needs treatment. Best is to see an endocrinologist right away, to determine severity and cause.