For something (actor CV- + -um-) to make a loud rumbling noise (theme), as of a loud clap of thunder, huge boulders falling down a mountainside.
CV- + -um-: bumibintūug
mumbibintūug
sup. ma'abbibintūug.
Loudly rumbling, as described above.
Mumbibintūug din batu an napūlig ad ugga ya timmā'ota'.
That stone which rolled yesterday rumbled loudly and I was afraid.