I. na‧sal¹ /ˈneɪzəl/ adjective
[Date: 1600-1700; Language: Medieval Latin; Origin: nasalis, from Latin nasus 'nose']

1. [only before noun] related to the nose:
the nasal passage

2. a sound or voice that is nasal comes mainly through your nose:
He spoke in a high nasal voice.

3. [only before noun] technical a nasal consonant or vowel such as /n/ or /m/ is one that is produced completely or partly through your nose
—nasally adverb

[TahlilGaran] Dictionary of Contemporary English ▲

II. nasal² noun [countable] technical
a particular speech sound such as /m/, /n/, or /ŋ/ that is made through your nose

[TahlilGaran] Dictionary of Contemporary English ▲