The quality or state of being glamorous; glamour as a characteristic.
From glamourous + -ness (noun-forming suffix for abstract qualities). Standard English derivation creating a noun that captures the essence or degree of glamour.
The 'ness' suffix is so productive in English that we can add it to almost any adjective to turn it into an idea—glamourousness is the abstract concept, while glamour is the concrete thing you see.
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