Offensive for the purpose of the survey means offensive language directed at a particular individual. That would include attacks based on nationality, personal characteristics etc etc (which we've seen in the past).

For the 2013/14 batch of reports, for both semesters, only 2 comments were removed because of being "offensive". The details are (email from the PhD student who processed the reports):

One said, "I wouldn't take this course again if you gave me free money". This sounded unnecessarily crass and other statements on the feedback for that course reflected this sentiment in more acceptable ways, so I felt nothing was lost by removing this one. The other edited comment contained a harshly-phrased personal attack. Again, other commenters responded with similar remarks, but in more toned-down language. These were more constructive comments, which I felt could be left in.

Now - personally I think the first comment (about the free money) could have been left in, and I mentioned that to my processor of the reports; however, I didn't push to re-create the report because he said the sentiment was reflected in other comments.

--mary