silly or nervous laughter about something, often at something you feel you should not be laughing at

Is this film any more than an hour and a half of tittering at rude jokes? 这部电影不过是对着粗俗笑话吃吃傻笑一个半小时，不是吗？

laughing in a silly or nervous way, often about something you feel you should not laugh at

She loathed his sarcastic smirk and tittering laugh. 她讨厌他挖苦的嘲笑和吃吃的傻笑。

This is a glimpse into the dirty mind of a tittering adolescent. 这让人瞥见一个吃吃傻笑的少年肮脏的心灵会是什么样子。