IPA: /ˈsɒmbərli/
KK: /ˈsɑːmbərli/
In a serious, sad, or gloomy way.
She spoke somberly at the memorial service.
Somberly → It is formed from "somber" (from Old French *sombre*, meaning dark or gloomy) and the suffix "-ly" (meaning in a manner of). The word "somberly" means in a dark or gloomy manner.
Think of the word 'sombre' which means dark or gloomy, and remember that 'somberly' describes doing something in a dark or gloomy way.