vagary /ˈveɪɡ(ə)ri 
, vəˈɡɛːri / ▸ (vagaries) noun (plural vagaries)
an unexpected and inexplicable change in a situation or in someone's behaviour: the vagaries of the weather.
– ORIGIN late 16th century (also as a verb in the sense ‘roam’): from Latin vagari ‘wander’.
EnglishOxford Dictionary of English
