noun
total area; total land area; square measure
Refers to the entire surface area of a piece of land, a building, or a region. Often used in real estate, geography, and official descriptions.
この土地の全面積は約500平方メートルです。
The total area of this land is about 500 square meters.
日本列島の全面積は約37万平方キロメートルだ。
The total area of the Japanese archipelago is about 370,000 square kilometers.
総面積 is a near-synonym also meaning 'total area', but 全面積 may emphasize the entire surface as a single unit.
Compound of 全 (zen, 'whole') + 面積 (menseki, 'area'). The reading is the standard on'yomi combination.