The phrase "chuck up" can be used in various ways such as to vomit or to abandon an idea. However, there are several synonyms for this phrase that can be used depending on the context. For example, "throw up" can be used instead of "chuck up" to express the action of vomiting. Similarly, "give up" or "abandon" can be used instead of "chuck up" to mean abandoning an idea or a plan. Alternatively, "surrender" or "relinquish" can also be used in a similar context. In conclusion, there are several synonyms for "chuck up" depending on the meaning and context of the phrase.