There are several synonyms for the phrase "clap up" that one can use in various contexts. First, one can use the term "applaud" to mean the same thing as clapping up. This term is commonly used in a formal setting, like during an awards ceremony, to show appreciation for someone or something. One can also use the phrase "cheer up" to mean the same as clamping up. It can be used in situations where one wants to cheer someone up or encourage them. Lastly, one can use the term "rejoice" to celebrate something, like a victory or achievement, instead of using the phrase "clap up".