1) Fierceness 2) French word used in English 3) Furiousness 4) Fury 5) Intensity 6) Intensiveness 7) Savageness 8) Savagery 9) Vehemence 10) Violence 11) Wildness Found on https://www.crosswordclues.com/clue/ferocity
Fe·roc'i·ty noun [ Latin ferocitas , from ferox , -ocis , fierce, kin to ferus wild: confer French ferocité . See Fierce .] Savage wildness or fierceness; fury; cruelty; as, ferocity of countenance. « The pride and ferocity of a Highl... Found on http://www.encyclo.co.uk/webster/F/20
ferocity 1. Characterized by being wild or turbulent. 2. Savage wildness or fierceness; fury; cruelty: 'They saw the ferocity of lions fighting over the dead antelope.' 3. Fierceness indicating a savage heart. Found on http://www.wordinfo.info/words/index/info/view_unit/3874/