In season 3 of Magical Girl Lyrical Nanoha, Hayate calls Reinforce "Rein", and near the end of season 2 she renames Dark Book to Reinforce. However, looking at the text, it looks like "re-in-force" rather than "rein-force".
So, I am wondering if "rein-force" is actually how Reinforce is supposed to be called or if it's supposed to be "re-in-force", which however sounds different due to it being said by the Japanese.