• 微笑びしょう — gentle smile
• 苦笑くしょう — bitter smile
• 爆笑ばくしょう — burst of laughter
• 冷笑れいしょう — sneer / cold smile
• 笑顔えがお — smiling face
• 失笑しっしょう — involuntary laugh

笑 combines the bamboo radical ⺮ with the phonetic element 夭. Originally it suggested lightness and swaying, like bamboo in the wind, which was associated with laughter and smiling as a gentle release of emotion. Over time it became the standard character for laugh and smile.

彼かれの 話はなしで 皆みんなが 笑わらいました。
Everyone laughed at his story.

笑顔えがおが 素敵すてきですね。
Your smile is lovely.