serious, passionate, forceful, strong, extreme, great, fierce, severe, high, earnest, impassioned, fervent, zealous, vehement, fiery, emotional, foreboding, unease, anxiety, anxious, apprehension, trepidation, disquiet, uneasiness, misgiving, something bad is going to happen
1. of extreme force, degree, or strength.
"the job demands intense concentration"
Similar: great, acute, enormous, fierce, severe, extreme, high, exceptional, extraordinary, harsh, strong, powerful, potent, vigorous, major, profound, deep, concentrated, consuming, serious
2. having or showing strong feelings or opinions; extremely earnest or serious.
"an intense young woman, passionate about her art"
Similar: passionate, impassioned, ardent, earnest, fervent, fervid