the world > textiles and clothing > clothing > types or styles of clothing > clothing for body or trunk (and limbs) > [noun] > shirt > part of > collar > types of (3)
a high stiff shirt collar with the upper corners turned down.
(a) a shirt collar whose points are held down by buttons or other fastenings (cf. button-down, adj. 2a); (b) (see quot. 1957).