The principal meaning of 'fulsome', the ever-handy Macquarie Dictionary tells us, is "lavish, unstinted". However, the correct spelling doesn't include a lavish number of Ls. In other words, don't spell it 'fullsome'.
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This mistake pops up with some frequency online. Here's a recent example from the Daily Telegraph:
He says there was a "fullsome and detailed discussion" in setting the guidance framework.
No, there wasn't.
Words with 'full' at the front of them generally use a hyphen (such as 'full-fledged' or 'full-blown'). The only example in English that the Macquarie lists which starts with 'full' and no hyphen with a double-L is 'fullness'. That makes 'fulsome' an annoying exception, but annoying exceptions are a frequent curse for English speakers. We have to deal with them. Accuracy matters.
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