This is the 13919th most frequent Spanish word.
solitarias
"Solitary" or "lonely."
Here, 'solitarias' is used as an adjective modifying 'calles,' describing them as deserted or unpopulated.
Ella pasea por las calles solitarias al anochecer.
She strolls through the lonely streets at dusk.
In this case, 'solitarias' characterizes the subject's afternoons as quiet and introspective.
Sus tardes siempre eran solitarias, llenas de pensamientos y recuerdos.
Her afternoons were always solitary, filled with thoughts and memories.
Here, 'solitarias' describes the flowers in the garden as being isolated or standing alone, emphasizing their uniqueness or beauty.