Button up and Buttoned-down

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

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

Buttoned-down adjective - Unimaginatively conventional.

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