Meaning of “unfavourable” - Learner’s Dictionary

unfavourable

adjective UK (US unfavorable) uk us /ʌnˈfeɪvərəbl/
CRITICIZING

negative and showing that you do not like something:

unfavourable publicity
NOT GOOD

not good and likely to cause problems:

unfavourable weather conditions
unfavourably adverb

(Definition of “unfavourable” from the Cambridge Learner’s Dictionary © Cambridge University Press)