Truancy is any intentional, unjustified, unauthorized, or illegal absence from compulsory education. It is a deliberate absence by a student's own free will and usually does not refer to legitimate excused absences, such as ones related to medical conditions. Truancy is usually explicitly defined in the school's handbook of policies and procedures. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.