keep down
• stay hidden by crouching or lying down.
• "Keep down! There's someone coming"
• cause something to remain at a low level.
• "the population of aphids is normally kept down by other animals"
• retain food or drink in one's stomach without vomiting.
• "all I could keep down was water"
• cause someone to remain in a state of oppression or subjection.
• "others doubted the injury would keep him down that long"
• make a pupil repeat a year at school because of poor marks.
• "is a child who fails a year test to be kept down?"
