It comes from the Proto-Indo-European root *ten-, meaning "to stretch, extend, hold". This root has given rise to many words in English and other languages related to holding, containing, or preserving.
Here are some examples of words with the root "ten":
* Tenant: One who holds or occupies property.
* Tenacious: Holding fast; persistent.
* Tenable: Able to be held or defended.
* Retention: The act of holding or keeping something.
* Detention: The act of being held or kept, especially as a punishment.
Keep in mind that the meaning of the root can sometimes change slightly depending on the word it's part of.