倦み疲れる[umitsukareru] to grow weary
倦厭[kenen] weariness
倦怠[kentai] languor
倦怠感[kentaikan] physical weariness
倦怠期[kentaiki] the stage of fatigue

倦憊[kenpai] extreme fatigue
倦む[agumu] to get tired of (doing)
倦る[akiru] to get tired of
攻め倦む[semeagumu] to lose the attacking initiative
待ち倦む[machiagumu] to tire of waiting

一張一弛[icchouisshi] tension and relaxation
弛む[yurumu] to become loose
弛み[tarumi] slack
弛む[tarumu] to slacken
中弛み[nakadarumi] a slump

弛緩[shikan] relaxation (e.g. of muscles)
弛張振動[shichoushindou] relaxation oscillation
筋弛緩剤[kinshikanzai] muscle-relaxant drug
弛まない[tayumanai] untiring
腕弛るい[kattarui] listless