The term 'stand firm' can be expressed in a variety of ways. The first is 'INSIST', which is a 6 letter word meaning to demand something firmly and persistently. The second is 'DEFY', which is a 4 letter word meaning to resist or refuse to obey. The third is 'put one's foot down', which is a 15 letter phrase meaning to take a strong stance on an issue. Finally, the fourth is 'stick to one's guns', which is a 15 letter phrase meaning to remain resolute and not give in to pressure. All of these terms express the idea of standing firm and not giving in to opposition.