幻を追う[maboroshiwoou] to pursue an illusion
幻影[genei] phantom
幻覚[genkaku] hallucination
幻覚剤[genkakuzai] hallucinogen
幻姿[genshi] apparition

幻視[genshi] visual hallucination
幻想[gensou] illusions
幻想劇[gensougeki] non-realistic drama
幻像[genzou] phantom

クスクス笑う[kusukusuwarau] to giggle
けらけら笑う[kerakerawarau] to cackle
げらげら笑う[geragerawarau] to guffaw
一笑[isshou] laugh
一笑に付す[isshounifusu] to laugh (someone) down

一顰一笑[ippinisshou] (a) mood
可笑しい[okashii] funny
含み笑い[fukumiwarai] suppressed laugh
嬉笑[kishou] happy laughter
戯笑[gishou] playful laughter