A chunk of ice or hard slush, usually
dark brown, which is found
in the middle of, or alongside, the road in winter, having
fallen off a passing car. It builds up like a stalactite behind the wheel from dirty road slush being thrown up there and sticking. Also known in some quarters as a slurd.
Dear
Uncle Pete... Weather was a bit warmer today so car boogers were in evidence
everywhere on the roads... kids were dodging cars and
running out to kick them apart on their way home from school.... p.s. Mom's hemorrhoids are acting up again.