威張り散らす[ibarichirasu] to domineer
胃散[isan] stomach medicine
逸散に[issanni] at top speed
一目散[ichimokusan] at full speed
一目散に[ichimokusanni] at full speed

雲散霧消[unsanmushou] vanishing like mist
解散[kaisan] breakup
拡散[kakusan] scattering
閑散[kansan] deserted (esp. store, market, town, streets)
言散らす[iichirasu] to spread (a report)

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