- opaque - not clear; not transmitting or reflecting light or radiant energy; "opaque windows of the jail"; "opaque to X-rays"
Antonyms: clear, crystalline, crystal clear, lucid, pellucid, transparent, hyaline, hyaloid, liquid, limpid, unfrosted, translucent, semitransparent, unclouded
- opaque, unintelligible - not clearly understood or expressed
Antonyms: comprehensible, comprehendible (indirect, via incomprehensible)