inimical

/ɪˈnɪmɪkəl/
adjective
  1. Harmful or unfavorable; tending to cause damage or hinder progress.
    • The constant noise was inimical to the students' concentration.
    • A lack of sleep is inimical to good performance at work.
    • Smoking is inimical to your health.
  2. Unfriendly or hostile in nature or attitude.
    • The rival companies had an inimical relationship for decades.
    • The two leaders exchanged inimical glances during the meeting.
    • Her inimical tone made it clear she did not want to cooperate.