passionate; with strong emotion
When the police asked him if he knew anything about the murder, he responded with a vehement denial.
vehemens vehementem (impetuous, eager, violent, furious, ardent) (Latin)
Vehement resembles cement i.e. strong, forceful (cement expands inwards with immense pressure and force) vehement == cement. ve (very)+he+men; try to remember as very manly; full of energy