The term 'put one's foot down' is an idiom that means to take a firm stance on something and not back down. The crossword solutions for this term are REV (3 letters), STOMPED (7 letters), TROD (4 letters), SPED (4 letters), BRAKED (6 letters), STEP (4 letters), STOMP (5 letters), DEMAND (6 letters), INSIST (6 letters), DEMANDED (8 letters), and INSISTED (8 letters). All of these words are related to the idea of taking a firm stance, such as revving an engine, stomping one's feet, trodding firmly, speeding up, braking, stepping, stomping, demanding, insisting, demanding again, and insisting again.