coherent
adjective
marked by an orderly, logical, and aesthetically consistent relation of parts
“a coherent argument”
Oppositesincoherentcapable of thinking and expressing yourself in a clear and consistent manner
“a lucid thinker”
“she was more coherent than she had been just after the accident”
(physics) of waves having a constant phase relation
Oppositesincoherentsticking together
“two coherent sheets”
“tenacious burrs”
Synonymstenacious
Source: WordNet 3.1, Princeton University