| ̷ ̷ ̷ ̷| ̷ ̷( ̷ ̷) ̷ ̷ adjective
: having complete or decisive mastery : dominant , overriding
some overmastering motive which he could not guess at — John Buchan
choking down some overmastering emotion — A. Conan Doyle
• over·mas·ter·ing·ly adverb