An arabic women wearing a veil that hides the whole of here body except her eyes. The term "Letterbox" comes from the fact that the slit where the eyes are seen looks like that on a letterbox.
That Letterbox Woman over there was just sick in her veil"
With its roots in Dartmoor in England, Letterboxing involves a waterproof box hidden in a scenic location and containing a rubber stamp and notebook; a person uses a series of clues (some are more cryptic than others) and possibly a compass and map to search for a box. Once found, the finder will stamp the box's notebook with his or her personal stamp, and use the box's stamp to mark their own personal notebook. Letterboxers collect the stamps from boxes all over the world. Similar in some ways to geocaching.
"I just got a patch for collecting my first hundred letterboxes!"
Tribadism or the lesbian act of rubbing two vulvae together (commonly known as scissoring) when practiced in secret by two Muslim lesbians.
The term is inspired from the comment, considered derogatory by some, by British politician Boris Johnson, who described Muslim women wearing burkas as looking like letterboxes. Given the parallels between a woman in a burka being hidden away from society and lesbianism not being able to be practiced openly in Islamic communities, as well as the colloquial description of a woman’s vagina as a box, this term to describe this sexual act seems particularly poignant.
It is not just their faces that need to be hidden from society. When Fatima and Aisha indulge in some hot letterboxing it’s inevitably conducted behind closed doors. Sadly, there’s no scope for perverts like me to get a sneaky peak.