ADVENTITIOUS
Meaning of ADVENTITIOUS in English
ad ‧ ven ‧ ti ‧ tious /ˌædvənˈtɪʃəs◂, ˌædven-/ BrE AmE adjective formal
happening by chance SYN unexpected
—adventitiously adverb
Longman Dictionary of Contemporary English.
Longman - Словарь современного английского языка.
2012