get a word in edgewise

3. get a word in edgewise, to succeed in entering a conversation or expressing one’s opinion in spite of competition or opposition: There were so many people talking at once that I couldn’t get a word in edgewise.

see edgeways.

Also, get a word in edgeways. Insert oneself into a conversation or express one’s opinion despite competition from other speakers. For example, So many people had questions for the lecturer that it was hard to get a word in edgewise, or Nancy loves to talk, and I couldn’t get a word in edgeways. This idiom, often put in the negative, transfers an object with its edge foremost to inserting conversation. [Late 1700s]

see get a word in edgewise.