不透明【ふとうめい】
opaque, obscure, murky, turbid, opacity, obscurity, unclear, unpredictable, uncertain
透明【とうめい】
transparent, clear
浸透【しんとう】
permeation (of thought, ideology, culture, etc.), infiltration (e.g. of ideas), spread, penetration (e.g. into a market), pervasion, permeation (of a liquid, etc.), soaking, percolation, osmosis
透き通る【すきとおる】
to be transparent, to be see-through, to be clear, to be clear (voice, sound)
透視【とうし】
seeing through, fluoroscopy, roentgenoscopy, clairvoyance, seeing through (objects), second sight