The act of smacking another's forehead as a sign and act of derision.

cranium, skull, brain case, brain box

someone stupid or someone performing an activity with seemingly no intelligence

Single breast. See melons

An ironic term used for a nerd with small breasts.
boobsnerdinsultdatelessegghead

1. A yellow, round and juicy fruit that is usually about the size of a football. It is commonly sliced up and de-seeded before serving. There are quite a few variants of the fruit including the popular water melon

shortened form of "meddling" or "meddling with"