Is one spelling mistake in the academic CV a big deal? Just after submitting my CV to graduate school for masters admission, I realized that there was one spelling mistake on the first page of my CV. I misspelled the word 'merchandising'(missed the h). Is it going to be a major issue for my application?
I'll give the same answer as Allure, but for a very different reason. Not only is it common, but most people won't notice it. And of the few that do, fewer yet would think it an important enough issue to bother with. 

"Egad, this person misspelled a word. Horrors." 

Nope, it ain't gonna happen. 

But, you also need to be assured that no single thing, whatever it is, would likely derail an application (yes, a few obvious exceptions). Your acceptance is based on a judgement and the judges try to look at a complete picture of an applicant; both their past accomplishments and the likelihood of success in the future. The CV (as a whole), your statement of purpose, your grades and test scores, your letters of recommendation. Each of those contribute to a (fairly) complete picture. Flaws or issues in one part can be balanced and overcome by the positive and supporting parts elsewhere. 

Relax. The judges are no more perfect than you are.