sermonette
/ˌsɜːrməˈnɛt/Definitions
1. noun
a short sermon or a brief address, often given in a casual or informal setting
“The pastor delivered a sermonette to the community during the town festival.”
2. noun
a small or minor sermon, especially one that is not part of a regular church service
“The visiting missionary gave a sermonette to the children at the local orphanage.”