번잡해요 · 번잡했어요 · 번잡한 (+noun)
crowded and hectic, congested; complicated
Example
주말에는 시내가 너무 번잡해요.
Downtown is too crowded on weekends.
Word parts
번 bothersome+잡 mixed
Literally 'bothersome and jumbled'.
Good to know
번잡하다 is negative (too hectic); 번화하다 is positive (lively, bustling).