The phrase "has the quivers" refers to feeling nervous or shaky. Some antonyms for this phrase could include feeling calm, composed, collected, confident, steady, secure, or serene. These words indicate a sense of stability and confidence, as opposed to the uneasy feeling that "has the quivers" implies. Other antonyms could include fearless, bold, decisive, unwavering, resolute, or determined. These terms indicate a sense of strength and courage, rather than the vulnerability and wavering that comes with having the quivers. Overall, antonyms for "has the quivers" suggest a confident, steadfast demeanor.