to increase the severity, violence, or bitterness of; aggravate
This word appears in the same article as a prior word of the day, plangent. Here is the quote for exacerbate: “Should there be a pandemic, Tamiflu would be in short supply. You should not exacerbate that shortage by abetting hoarding.” One time when I was a teacher I used this word in the classroom, and a bunch of the students started snickering. I had half a mind to tell them that if they kept laughing they’d go blind.