下腹部

lower abdomen

down / downwards / below / lower / later / next (week etc) / second (of two parts) / to decline / to go down / to arrive at (a decision, conclusion etc) / measure word to show the frequency of an action

abdomen / stomach / belly

abdomen / belly / flank

ministry / department / section / part / division / troops / board / classifier for works of literature, films, machines etc