Difficult to deal with; prone to erratic behavior.unpredictable, temperamental, emotional, volatile, capricious, changeable, mercurial, unstable, fickle, flighty, inconstant, undependable, unsteady, erratic, fitful, impulsive
Mid 16th century from kittle ‘to tickle’ (now Scots and dialect), probably from Old Norse kitla.
intransitive verb[no object]Scottish, Northern Irish
(of a cat) give birth.‘she has kittled in my chair’
Mid 16th century perhaps a back-formation of kitling ‘young animal, cub’.
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