From Old Dutch *thunken, from Proto-Germanic *þunkijaną. Cognate with Old English þyncan (English think), Old Saxon thunkian, Old High German dunken (German dünken), Old Norse þykja (Swedish tycka), Gothic 𐌸𐌿𐌲𐌺𐌾𐌰𐌽 (þugkjan).
Dunken is one of a few Dutch verbs where the object is the one having an opinion about something, and the subject is the thing it concerns. For example, het dunkt mij goed means 'I think/consider it good'. For this reason it is generally used impersonally.
The past tense forms are archaic and rarely used.