1. occurring in spells and often abruptly - fitful bursts of energy - spasmodic rifle fire • Syn: spasmodic • Similar to: sporadic • Derivationally related forms: fitfulness 2. intermittently stopping and starting - fitful (or interrupted) sleep - off-and-on static • Syn: interrupted, off-and-on • Similar to: broken • Derivationally related forms: fitfulness