Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!

Qenya 

tundo

noun. hill, mound, hill, mound [isolated]

A noun in The Etymologies of the 1930s glossed “hill, mound” derived from the root ᴹ√TUN (Ety/TUN). Tolkien’s continued use of Q. Túna for the name of a hill in Valinor implies the ongoing validity of its root, so perhaps this word remained valid as well.

Neo-Quenya: For purposes of Neo-Quenya, I would assume that tundo refers mainly to a single isolated hill standing out from its surroundings, as opposed to Q. ambo for hills in general, but that’s speculation on my part.

Cognates

  • N. tunn “hill, mound” ✧ Ety/TUN

Derivations

  • ᴹ✶tundu “hill, mound” ✧ Ety/TUN
    • ᴹ√TUN “*tall; mound” ✧ Ety/TUN

Phonetic Developments

DevelopmentStagesSources
ᴹ✶tundu > tundo[tundu] > [tundo]✧ Ety/TUN

Variations

  • tundo ✧ Ety/TUN

ambo

noun. hill

Cognates

  • N. amon “hill” ✧ Ety/AM²

Derivations

  • ᴹ√AM “up” ✧ Ety/AM²

Phonetic Developments

DevelopmentStagesSources
ᴹ√AM² > ambo[ambo]✧ Ety/AM²