This is the 6014th most frequent Portuguese word.
co
"Co" is not an independent word in Portuguese; it is often a prefix meaning "with" or "together" (e.g., "coautor" = "co-author").
In this sentence, 'coelho' means 'rabbit', and the prefix 'co-' is part of the word's root form, which does not indicate a standalone meaning.
O coelho saltou rapidamente pelo campo.
The rabbit jumped quickly across the field.
Here, 'colaboração' means 'collaboration', and the prefix 'co-' signifies a connection or joint action between entities.
O trabalho em equipe promove a colaboração.
Teamwork promotes collaboration.
In this case, 'colar' means 'necklace', and the prefix 'co-' constitutes part of the whole word, without an independent meaning.