Dynamic classification allows objects to change type within 
the subtyping structure whereas static classification does 
not Ex:for dynamic classification is person's job(It can 
change).EX:for static classification sex.(male & female).

static means constant. Dynamic means randomly we can change 
in genral sences. So, static diagram we can not change it 
si fixed attributes but dynamic diagram we can change. As 
given example:- person job is attribut we can change the 
job . so, it is dynamic but sex of person male / female we 
canot change it is static