During gardening, the (mainly) unintentional deaths and injuries of innocent snails, from damage that is caused to their shells as they cling helplessly to exposed walls and paving.
"Spent Saturday afternoon weeding the flower beds. The shellateral damage was extensive."
Oral sex performed upon a female. Usually used to refer to a recipient who has an enlarged clitoris. Shellatio (pronounced she-latio) is a variation of 'fellatio'. The act itself is more similar to stimulating a male than an average female, hence the similarity in the name.
"I thought it'd be great to go down on Betty, but when I finally saw her gigantic clit, I realized I'd better be ready for some shellatio!"