Collocations for bun - noun

fresh | stale | cinnamon, cream, currant, hot cross, iced, sticky | hamburger

eat, have | bake, make

neat, severe, tight | loose

in a ~
a woman with her hair in a loose bun

pull/draw your hair back in(to) a bun
Her black hair was drawn back into a neat bun.

tie your hair (back) in a bun, wear your hair in a bun