This is the 12742nd most frequent Spanish word.
ocasionalmente
Occasionally.
Here 'ocasionalmente' is used as an adverb to denote the frequency of the action described ('visitar' = 'to visit').
Ocasionalmente visito a mis amigos los fines de semana.
Occasionally, I visit my friends on weekends.
In this example, 'ocasionalmente' indicates an adverbial temporality regarding the reflection caused by sunlight.
La pintura en esa pared ocasionalmente refleja la luz del sol.
The paint on that wall occasionally reflects sunlight.
The word 'ocasionalmente' is used to describe the frequency of finding interesting books (verb 'encontrar' = 'to find').