Webster's 1828 Dictionary
RESTLESSNESS
n. 1. Uneasiness; unquietness; a state of disturbance or agitation, either of body or mind.
2. Want of sleep or rest; uneasiness.
3. Motion; agitation; as the restlessness of the magnetic needle.
American Oxford Thesaurus
restlessness
restlessness noun an excess of the herb may cause headaches and restlessness: unease, restiveness, edginess, tenseness, nervousness, agitation, anxiety, fretfulness, apprehension, disquiet; informal jitteriness.
Oxford Thesaurus
restlessness
restlessness noun 1 at lunch there was an odd restlessness among his pupils: unease, restiveness, fidgetiness, edginess, tenseness, nervousness, agitation, anxiety, fretfulness, discomposure, jitteriness, apprehension, unquietness, disquiet, disquietude, impatience. ANTONYMS calm. 2 a walk outside might help night restlessness: sleeplessness, insomnia, wakefulness; archaic watchfulness. ANTONYMS repose, sleep.