mapku -map- gismu

x₁ is a cap/hat/crown/helmet/piece of headgear [head-top garment] of material x₂.

In notes:

drudi: x₁ is a roof/top/ceiling/lid of x₂.
stedu: x₁ is a/the head [body-part] of x₂; [metaphor: uppermost portion].
taxfu: x₁ is dress/a garment/clothing for wearing by x₂ (gender/species/body part) serving purpose x₃.
badmapku: x₁ is a helmet, protective cap
mapypre: p₁ is a hatter/millner /[hat maker] selling/making hats of material m₂.
nipmapku: m₁=s₁ is a beanie hat of material m₂.
nolmapku: m₁ is a crown made of m₂.
slanymapku: m₁=s₁ is a top hat [cylindrical hat] made of material m₂=s₂.
trumapku: m₁ is a crown made of m₂ used by ruler t₁ of people/territory/domain/subjects t₂.
maprtrilbi: x₁ is a trilby / trilby hat of material x₂.