nail one's colours to the mast

Alternative forms

• pin one's colours to the mast

Etymology

From the naval military practice of displaying one's colours (signal flags or insignia) from the mast of a ship during battle to show loyalty. To surrender, one would strike one's colours, i.e. take down one's flag. If a ship nailed its colours to the mast, it would fight to the death and not surrender.

Verb

nail one's colours to the mast (third-person singular simple present nails one's colours to the mast, present participle nailing one's colours to the mast, simple past and past participle nailed one's colours to the mast)

1. To clearly show one's support for a side or opinion in a dispute, often indicating an intention to defend that side to the end.

See also

• show one's true colors