瞳孔[doukou] pupil
瞳子[doushi] pupil
瞳を凝らす[hitomiwokorasu] to strain one's eyes
瞳孔拡張[doukoukakuchou] pupil dilation
瞳孔散大[doukousandai] dilation of the pupil

散瞳[sandou] mydriasis
縮瞳[shukudou] miosis
散瞳薬[sandouyaku] mydriatic agent
瞳孔縮小[doukoushukushou] pupil contraction

あっ縮[asshuku] compression
圧縮空気[asshukukuuki] compressed air
圧縮性[asshukusei] compressibility
圧縮率[asshukuritsu] compressibility
畏縮[ishuku] wince

音声圧縮[onseiasshuku] voice compression
強縮[kyoushuku] tetanus
恐縮[kyoushuku] feeling obliged
凝縮[gyoushuku] condensation
緊縮[kinshuku] shrinkage