The phrase "take a stab" means to make an attempt or try at something. Antonyms for this phrase might include giving up, abandoning, quitting, or surrendering. Other antonyms might include avoiding, evading, or ignoring something altogether. When someone uses the phrase "take a stab," they are typically expressing a willingness to take a risk or try something new, so antonyms might also include words that suggest someone is being cautious or hesitant, such as hesitating, doubting, or waffling. Ultimately, the antonym of "taking a stab" will depend on the context of the conversation or situation.