To obtain or secure something desired, favorable, or profitable. She gained a lot of experience working in the industry.
To increase in amount, size, or degree. The stock gained 5% in value over the last month.
To reach or arrive at a destination, especially with effort. They gained the summit after a long and arduous climb.
Of a timepiece, to run fast, showing a time later than the correct time. This cheap wristwatch gains nearly five minutes every day.