The opposite of "smiles up on" can be various expressions that denote sadness, disappointment, or anger. Some antonyms that convey sadness are frowns, scowls, grimaces, and tears. These expressions are often associated with negative emotions like sorrow, grief, and despair. When one is disappointed, the opposite of "smiles up on" could be expressed through the words like sulks, pouts, glowers, and mopes. On the other hand, if one is angry or frustrated, antonyms like snarls, sneers, glares, and seethes can be used to depict the opposite of smiling up on. Overall, antonyms of "smiles up on" depend on the underlying emotion being conveyed.