To groan repeatedly about or to express loud sorrow or complaint about something.
From be- (prefix) + groan (from Old English grānian, imitative in origin, meant to reproduce the sound of heavy sighing or moaning).
Groan is one of English's onomatopoeia words—it literally imitates the sound people make. The 'be-' prefix suggests doing this repeatedly and intensively, like bemoaning a situation.
Complete word intelligence in one call. Free tier — 50 lookups/day.