Definition of nasalize in English:

nasalize

(also nasalise)

verb

[WITH OBJECT]
  • Pronounce or utter (a speech sound) with the breath resonating in the nose.

    ‘a nasalized vowel’
    • ‘In southern England, the vowel is nasalized and long.’
    • ‘But after, for example, verbs ending in ‘a’, ‘en’ gloms onto the verb and turns the final ‘a’ into an ‘eh’ sound, creating a long, nasalized ‘eh’.’
    • ‘In speech, hard ‘r’ frequently gets nasalized, in the same way as ‘k’ becomes aspirated in the American throat.’
    • ‘Also, the nasal cavity can be closed thus preventing vowels from being nasalised and thus increasing their comprehensibility.’
    • ‘The first small problem with the Reuters article is that the usual spelling for the language is ‘Pirahã’, with a tilde over the final /a/, indicating that the vowel is nasalized.’
    • ‘French is essentially a language that elides everything that doesn't get out of the way fast enough, and nasalises everything else.’
    • ‘Try saying ‘cromps,’ while nasalizing the m a little, like in French.’

Pronunciation:

nasalize

/ˈneɪz(ə)lʌɪz/