Severe
Part of speech: adjective
Definition: Very bad or intense. Strict or harsh.
Example sentence: In so far as the mind is stronger than the body, so are the ills contracted by the mind more severe than those contracted by the body.
Intense
Part of speech: adjective
Definition: Strained; tightly drawn; kept on the stretch; strict; very close or earnest; as, intense study or application; intense thought.Extreme in degree; excessive; immoderate; as: (a) Ardent; fervent; as, intense heat. (b) Keen; biting; as, intense cold. (c) Vehement; earnest; exceedingly strong; as, intense passion or hate. (d) Very severe; violent; as, intense pain or anguish. (e) Deep; strong; brilliant; as, intense color or light.
Example sentence: I became more aggressive, more dedicated, more intense - taking it match by match, night by night - to literally crawl and scratch my way back to the top.