(verb): to brick is when you kill a small animal by way of crushing its cute little skull (or whole body if its small enough) with a brick. Usually done as a mercy kill if a baby bird/squirrel/mouse/runt puppy/kitten is injured/falls out of a tree/or is sick. It is a highly effective, painless, but no doubt very gruesome and messy way to off a small animal. It can be effective against larger animals, like humans (infants or adults)or full grown dogs/cats/etc. but only when used in conjunction with the element of surprise...
Hey daddy, I found this baby squirrel on the ground, can we take him to the vet to make him better?
"Sure, son, let me take him, be back in a few with a 'good as new squirrel baby'"
(exit dad with squirrel and brick in hand).