This is the 5224th most frequent Portuguese word.
plana
"Plana" means "flat" or "level" in English.
Here, the word 'plano' appears as a noun referring to a structured idea or course of action (note the gender difference between nouns and adjectives in Portuguese).
Ela traçou um plano detalhado antes de viajar.
She devised a detailed plan before traveling.
The verb 'planeja' (derived from 'planar') is used here to express the act of planning, demonstrating the lexical root associated with 'plana'.
Ele sempre planeja suas atividades cuidadosamente.
He always plans his activities carefully.
In this sentence, the word 'plana' functions as an adjective describing the flatness or evenness of the table's surface.