underbrims
/ˈʌndərbrɪmz/
noun
- The lower or inner edges of a hat's brim, especially the part that touches the head or is visible from below.
- The hat's underbrims were lined with soft velvet for comfort.
- He wiped the sweat from the underbrims of his cowboy hat.
- She decorated the underbrims of her sun hat with small silk flowers.