What does "syllabicity" mean?

The property or status (of a syllabic, generally a vowel) of being syllabic, i.e. able to be positioned in the syllable nuclei.

How do you pronounce "syllabicity"?

Pronounced //ˌsɪləˈbɪsɪti//.

/ˌsɪləˈbɪsɪti/ noun

noun ·Rare ·Advanced level

Noun

1
The property or status (of a syllabic, generally a vowel) of being syllabic, i.e. able to be positioned in the syllable nuclei. uncountable
"The syllabicity of Proto-Indo-European syllabic sonorants *y and *w can easily be determined by a rule."
2
the pattern of syllable formation in a particular language wordnet

"The syllabicity of Proto-Indo-European syllabic sonorants *y and *w can easily be determined by a rule."

From syllabic + -ity.