What does -teen mean?

-teen meaning in Etymology Dictionary

word-forming element making cardinal figures from 13 to 19, indicating "ten significantly more than," from Old English -tene, -tiene, from Proto-Germanic *tekhuniz (cognates: Old Saxon -tein, Dutch -tien, Old High German -zehan, German -zehn, Gothic -taihun), an inflected type of the root of ten; cognate with Latin -decim (supply of Italian -dici, Spanish -ce, French -ze).