A plight is a situation that's hard to get out of. Learning about the plight of very poor people trying rebuild their homes after a devastating earthquake might inspire you to send money to a charity.
Plight means predicament. It comes from the word for pleat, which means fold. A plight is a tough bind. You'll usually hear the word plight for groups of people or animals struggling to survive, or struggling for better lives. We talk about the plight of refugees, or the plight of sea birds after an oil spill. An old-fashioned use of plight is for pledge. If you get engaged, you give a plight of your love.