The Proto-Altaic word *tīdu
Word *tīdu
Meaning elevated ground, hill, mountain

Comments
Evenki ǯīdi (dial. didi) ‘mountain ridge’; Lamut / Even (Okhotka) gidan ‘mountain ridge’ (= /didan/ ?); Ulch ǯịdụ ‘mountain ridge’; Orok ǯịdụ(n) ‘mountain ridge’;

Other words that might be of interest
*bŏru ‘dust, smoke, whirlwind’, *pʰāla ‘field, level ground’, *biălu ‘dirt, mud’