unfriendly

(a) not easy to understand or use
- user-unfriendly
(a) not disposed to friendship or friendliness
- an unfriendly coldness of manner
- an unfriendly action to take
(s) not friendly
- an unfriendly act of aggression
- an inimical critic
inimical,
(s) very unfavorable to life or growth
- a hostile climate
- an uncongenial atmosphere
- an uncongenial soil
- the unfriendly environment at high altitudes
uncongenial, hostile,

inimical uncongenial hostile

friendly