1.Parents brother who, having paedophaelic (and sometimes homosexual) tendancies, often crept into your room late at night while drunk to 'play' with you under the covers. Can be characterised by using phrases such as "This can be our little secret," or "don't tell Mummy and Daddy." 2.Paedophile or rock spider
. 3.Sexually devious or sick induvidual.
1.I have a sneaky uncle. 2.There was a sneaky uncle creeping around our schoolyard.