He āhuatanga mokowā. Kotahi anake te ahunga o tētahi rārangi, ko tōna roa. E rua ngā ahunga o tētahi papa - ko tōna roa me tōna whānui. E toru ngā ahunga o tētahi matarau, arā, ko te roa, te whānui me te teitei.
A spatial property. A line only has one dimension, its length. A plane surface has two dimensions, its length and breadth. A solid has three dimensions, its length, breadth and depth.