"Unexcused" means that something is not justified or explained. It refers to an action or absence that is not given a valid reason or excuse. Full definition
Secondary students with 10 or more unexcused absences in any class during a single advisory shall receive a grade of «FA» in that subject. (dcps.dc.gov)
Three days of unexcused absences results in the virtual school reporting that student as a «truancy case» to the student's local public school district. (ncpolicywatch.com)
Secondary students with five (5) or more unexcused absences in any class during a single advisory shall receive a grade reduction in that subject. (dcps.dc.gov)