Button up and Button-down

Button up verb - Refuse to talk or stop talking; fall silent.

Button-down and button up are semantically related. In some cases you can replace phrase "Button-down" with "Button up", this terms are similar.

Button-down adjective - Tending to favor established ideas, conditions, or institutions.

Button up and button-down are semantically related. Sometimes you can use "Button up" instead a verb phrase "Button-down".