1. (

• inexplicable ,
• incomprehensible ,

) incapable of being explained or accounted for; "inexplicable errors"; "left the house at three in the morning for inexplicable reasons" ;

2. (

• incomprehensible ,
• uncomprehensible

) difficult to understand; "the most incomprehensible thing about the universe is that it is comprehensible"- A. Einstein ;