The phrase "stick like a barnacle" implies being stubbornly or annoyingly clingy. The antonyms, therefore, are words that convey the opposite. Some antonyms for "stick like a barnacle" include "let go," "detach," "release," "freedom," "loose," "unleash," "separate," and "drop off." These words are synonyms of independence, detachment, and separation. Instead of sticking too close and being an annoyance, embracing the antonyms can be beneficial for letting go of something or someone that has become burdensome. Sometimes, it's essential to break free, detach, and move on for personal growth and development.