1) Absurd 2) Alogic 3) Credulous 4) Disjointed 5) Garbled 6) Inane 7) Incoherent 8) Inconsequent 9) Inconsequential 10) Inconsistent 11) Irrational 12) Random 13) Ridiculous 14) Unacceptable 15) Unlogical 16) Unreasonable 17) Unsound 1) Absurd 2) Crazy 3) Foolish 4) Groundless 5) Incoherent 6) Inconsequential 7) Intuitive 8) Irrational 9) Lacking orderly continuity 10) Making no sense 11) Nonrational 12) Not logical 13) Ridiculous 14) Silly 15) Unfounded 16) Unlogical 17) Unreasonable 18) Visceral 
• (a.) Ignorant or negligent of the rules of logic or correct reasoning; as, an illogical disputant; contrary of the rules of logic or sound reasoning; as, an illogical inference.
Il·log'ic·al adjective Ignorant or negligent of the rules of logic or correct reasoning; as, an illogical disputant; contrary of the rules of logic or sound reasoning; as, an illogical inference. -- Il*log'ic*al*ly , adverb -- Il*log'ic*al*ness
[adj] - lacking in correct logical relation
adjective lacking in correct logical relation
not logical; contrary to or disregardful of the rules of logic; unreasoning: an illogical reply.