The phrase "trample up on" means to walk heavily or step on something or someone with force, often causing damage or harm. Some synonyms for this phrase include crush, stomp, flatten, tread on, walk over, or run over. These synonyms all indicate a forceful action that may result in damage or injury. It is important to use caution and to be aware of your surroundings when walking or moving through crowded areas to avoid trampling on others. Additionally, it is always important to treat the environment with respect and to avoid trampling on plants or animals that may be living in the area.