1. inactivity
showing an unusual lack of energy
e.g. the general appearance of sluggishness alarmed his friends
Synonym: languorlethargyphlegmflatness
2. the pace of things that move relatively slowly
e.g. the sluggishness of the economy
the sluggishness of the compass in the Arctic cold
3. a state of comatose torpor (as found in sleeping sickness)