The idiom seems older than the writing; it may be called, if I understand the meaning of the preface, as old as the beginning of the thirteenth century, and certainly older than the reign of Denis, pode appellidarse coevo do seculo xiii.
Successos do Reino do Congo, no seculo xvii, pelo J.
Descobrimento, posse, e conquista do reino do Congo pelos Portuguezes no Seculo xvi, por J.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "seculo" in a variety of sentences. We hope that you will now be able to make sentences using this word.
