juggernautjug·ger·naut /ˈdʒʌgənɔːt-ərnɒːt/ noun [countableC]1a very large companyThe software juggernaut Microsoft will continue to lead the industry with its Windows operating system.
2something large and powerful that could be harmful to smaller thingsThe country has fast become an economic juggernaut.
3British EnglishBrETRANSPORT a very large truck