asthenia Play nounAbnormal physical weakness or lack of energy. SYNONYMS apathydormancydrowsinessdullnessenervationfatigueheavinessidlenessinactioninactivityindolenceinertialack of energylanguidnesslanguorlassitudelazinesslethargylifelessnesslistlessnesspassivitysleepinessslothslothfulnessslownesssomnolencetirednesstorpiditytorporweariness