noun
square metre, square meter
A1
Quadratmeter means 'square metre' (square meter), unit of area. Abbreviated m². Masculine noun: der Quadratmeter. Plural Quadratmeter (same form). Genitive singular des Quadratmeters adds -s. Declines regularly as shown. Used with numerals and units; treated as a countable measurement noun.
Examples
Die Wohnung ist 80 Quadratmeter groß.
The apartment is 80 square meters.
Das Grundstück war 500 Quadratmeter groß, sodass die Firma dort eine Halle bauen konnte.
The plot was 500 square meters in size, so the company was able to build a hall there.
Der Mietpreis gilt pro Quadratmeter.
The rent price applies per square meter.
Details
Mnemonics
Visualize a square with a measuring tape labelled 'm²'
Quadratmeter sounds like 'quad rat meter' — imagine four little rats measuring a square
Der/das Quadratmeter — historically both genders used; common default 'der' here
Notes
Sometimes used with either masculine or neuter article in colloquial usage; in many contexts 'der Quadratmeter' is standard.