Etymology

Uncertain. Could be from From Proto-Indo-European *ker-d 'short mountain', from *(s)ker- ‎(“short”). Otherwise from Latin quadrum or from Proto-Indo-European *kaito 'forest'. Compare Romanian codru, Aromanian coduru, Old Persian (H)ara-kadriš ‎(“mountain ravine”), Welsh cader ‎(“fortress”), Old Irish cathir ‎(“town, city”), Umbrian kateramu ‎(“congregation”), Bulgarian kótor ‎(kótor, “hurdle”), Gothic haiÞi ‎(haiÞi), Old High German heida 'heath'. For sense development from high ground to city compare Germanic *burg.