The quality of gushing; the state or condition of flowing forth abundantly or expressing emotion excessively.
From gushing (present participle of gush) plus abstract noun suffix '-ness', creating a noun form of the action itself.
When English speakers add '-ness' to gerunds (verbs used as nouns), they create abstract nouns about actions—'gushingness' captures the essence of the gushing process itself, distinct from just being 'gushy.'
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