a destructive insect or other animal that attacks crops, food, livestock, etc.
the tomato plant attracts a pest called whitefly
2
an annoying person or thing; a nuisance.
he was a real pest
informal：nuisancebotherannoyanceirritationirritantthorn in one's flesh/sidevexationtrialthe bane of one's lifemenacecurseproblemtroubleworryinconvenienceboregadflypainpain in the neckaggravationheadachecussnyaffskelfnudnikpain in the buttnarkblighterblister
