The phrase "cry river" is an informal term that means to weep or cry excessively. Antonyms or opposite words for this phrase would include terms such as "happy," "content," "delighted," "joyful," and "pleased." Instead of crying a river, one might be laughing, smiling, or feeling contentment. It is essential to note that some antonyms might be influenced by the context of the situation. For instance, a person could cry rivers of joy when they win the lottery, while they could also cry rivers of sadness when they receive terrible news. Therefore, it is important to consider the context when searching for appropriate antonyms.