This is the 9666th most frequent Portuguese word.
coçar
To scratch.
Here, 'coçar' is used as a verb to describe the action of scratching oneself due to an itch.
Eu vou coçar minhas costas porque estão coçando.
I am going to scratch my back because it is itchy.
Here, 'coçar' is used to describe the act of rubbing or scraping a surface with a motion, not due to itching.
Ele começou a coçar o chão com o pé nervosamente.
He started scratching the floor with his foot nervously.
In this case, 'coçar' represents a habitual action associated with contemplation or thinking.