bathos
noun
[ ˈbeɪθɒs ]
• (especially in a literary work) an effect of anticlimax created by an unintentional lapse in mood from the sublime to the trivial or ridiculous.
• "his epic poem has passages of almost embarrassing bathos"
Origin:
mid 17th century (first recorded in the Greek sense): from Greek, literally ‘depth’. The current sense was introduced by Alexander Pope in the early 18th century.