The term TEST PAPER can be broken down into two crossword solutions: LITMUS and EXAM. LITMUS is a type of paper that is used to test the acidity or alkalinity of a solution. It is usually used in laboratories and is made from a mixture of different plant extracts. EXAM is a shortened form of the word examination, which is an assessment of a person's knowledge or skills. Exams are often used in educational settings to evaluate a student's understanding of a particular subject.