This is the 2044th most frequent Arabic word.
اللبنانية
"The Lebanese" (feminine adjective or noun).
Here, the word 'اللبنانية' is an adjective that describes the noun 'المؤلفة', meaning 'the Lebanese (female) author'.
كتبت المؤلفة اللبنانية رواية رائعة.
The Lebanese author wrote a wonderful novel.
In this case, 'اللبنانية' acts as an adjective describing the noun 'السياحة', referring to 'Lebanese tourism' as a whole concept.
السياحة اللبنانية مزدهرة.
Lebanese tourism is flourishing.
Here, 'اللبنانية' is used as an adjective modifying 'الجمعية', indicating that the association is Lebanese.