As a child from our bookcase at home I remember a B- novel called :
'De Boekeniers.' For a long time I thought it had to do with 'boeken'(books). Later on I understood it was about pirats and that bucaneer was directly 'Dutchenized' to boekenier in the past.
A milder synonym for pirat/bucaneer in Dutch is zeeschuimer (sea skimmer).Are there more english synonyms?