aegrotat
/iːˈgrəʊtæt/noun
1- Brit. a certificate stating that a university student is too ill to attend an examination〈英〉（证明大学生因病无法参加考试的）疾病证明书。
1.1
- an examination pass awarded to a student having such a certificate（发给持有疾病证明书的学生）免考证。
词源
late 18th cent.: Latin， literally 'he is sick'.