kuppa

adjective shaking, unsteady, movable; AN.iii.128 (˚dhammo, unsteady, of a pāpabhikkhu) Snp.784; of a kamma: a proceeding that can be quashed Vin.ii.71 (also a˚). nt. kuppaṃ anger Vin.ii.133 (karis sāmi I shall pretend to be angry)
akuppa (adj.) and akuppaṃ (nt.) steadfast, not to be shaken, an epithet of arahant and nibbāna (cp. asankuppa); akuppa-dhammo Pp.11 (see akuppa). Akuppaṃ as freedom from anger at Vin.ii.251.

ger. of kuppati