Adjective
1. not easy to understand or use;
"user-unfriendly"2. not disposed to friendship or friendliness;
"an unfriendly coldness of manner""an unfriendly action to take"3. lacking warmth of feeling;
"a chilly greeting""an unfriendly manner"4. not friendly;
"an unfriendly act of aggression""an inimical critic"5. very unfavorable to life or growth;
"a hostile climate""an uncongenial atmosphere""an uncongenial soil""the unfriendly environment at high altitudes"