The word "debouches" means to emerge or exit from a narrow or constrained space. Some possible antonyms for this word might include terms such as "enters," "penetrates," or "introduces." Other antonyms might include words like "withholds," "constrains," or "restricts," which imply a withholding or limitation of movement or access. Depending on the context in which the word "debouches" is used, there are many different antonyms that could be appropriate. By considering the meaning and usage of this word, it is possible to identify a range of opposites that can help to expand one's vocabulary and understanding.