To have (an) embarrassing, unpleasant, damaging, or incriminating secret(s) from one's past. Primarily heard in UK. Even the most seemingly perfect people have some pretty shocking skeletons in their cupboards. She has a skeleton in her cupboard that could ruin her chance at being elected if the press were to find out about it. My agoraphobia has always been something of a skeleton in the cupboard for me.