You can always find a word that is perfectly OK in one language but rude in another, hence those emails circulating that contain pics of Eastern European and Asian brand names which sound rude in english.
From the point of view of the board, 'rude' is what the board's writer says is rude, though perhaps mods can set the allowable level of 'rudeness'.
Just remember, if you type a post and click Post and your posted post contains the word 'thingy' then most likely the board s/w decided you'd included a rude word.