Would it still be permissible to repeat the old one about the L-n-t-c who drowned himself while in Paris? Punchline, "he was in Seine"/"insane". Scared to write the "L Word" in full, or tell this weak pun in public, lest someone seize the opportunity to take offence at the essential word.

Much prefer the one about the Frenchman seeing the tide rising and saying, "Merci", though the play on sounds might only be instantly understood in Scotland.