Other forms: icecaps
An icecap is a type of glacier. It’s a large, permanent mass of ice that is so big it’s like a cap for the Earth. An icecap usually forms on a mountain and then slopes down the sides.
While icecaps are considered to be permanent features, they do change in size, growing and shrinking over time. Earth isn’t the only planet with icecaps — Mars has them, too. An icecap is smaller than 50,000 kilometers and an ice sheet is bigger. So the Earth’s polar icecaps are technically ice sheets but they’re referred to as icecaps. The melting of these and the many smaller icecaps is a serious problem — as they melt, sea levels rise.