Buttoned-up and Unflappable

Buttoned-up adjective - Having or showing a lack of friendliness or interest in others.

Unflappable and buttoned-up are semantically related. In some cases you can use "Unflappable" instead an adjective phrase "Buttoned-up".

Unflappable adjective - Not easily panicked or upset.

Buttoned-up and unflappable are semantically related. Sometimes you can replace phrase "Buttoned-up" with "Unflappable", this terms are similar.