Antonyms for the phrase "blow horn" include words that represent silence or calmness. Some antonyms for "blow horn" are whisper, hush, silence, and stillness. Other antonyms may include words like quiet, peace, serenity, tranquility, and calm. These antonyms represent the opposite of the noisy and loud nature of blowing a horn. While blowing a horn may be necessary in certain situations, a focus on the antonyms can help to create a more serene and peaceful atmosphere. Using these words can help to convey a sense of relaxation and calm while avoiding the use of loud noises.