1. A plane figure having four angles; a quadrangle; an aspect of two planets with regard to the earth when they are distant from each other 90

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• pedragon,
• retragon,
• fetragon,
• getragon,
• yetragon,
• 6etragon,
• tetreagon,
• tetragohn,
• tetragoon,
• tetregon,
• tetracon,
• tetraggonia,
• ceragoo,
• tetrdon,
• tetradont,
• Tetredont,
• Tetradond,
• tetragynus,
• tetrazzone,
• tetrazonee

• tetracaine,
• tetraspore,
• tetragonia,
• tetragram,
• tetraclinis,
• teeters,
• tetragonal.

The adjective form of the word "tetragon" is "tetragonal".

The plural form of the word "tetragon" is "tetragons"

The singular form of the word "tetragon" is "tetragon". Tetragon is both the singular and plural form of the word.