fall in. collapse, cave in.
falling away. emaciation, [pining]; [renunciation], [desertion], [revolt], [unfaithfulness]; [apostasy], defection, [backsliding]; [decline], declension.
falling back. recession, [retreat], [retirement], [withdrawal].
falling down. prostration, collapse.
falling in with. [meeting]; concurrence, [agreement], [compliance].
falling off. [dropping]; [withdrawal], [separation], [detachment]; [apostasy], defection, [desertion]; depreciation, [deterioration].
falling out. See quarrel.
falling short. [deficiency], inadequacy, deficit, [shortcoming].
falling sickness. epilepsy.
falling star. [meteor].