scle·ro·ma 
(sklə-rōmə)
(sklə-rōmə)n. pl. scle·ro·mas or scle·ro·ma·ta (-mə-tə)
An abnormally hard patch of body tissue especially in the upper respiratory tract.
[New Latin, from Greek sklērōma, hardening, from sklēroun, to harden, from sklēros, hard.]