You can overload program units by using different names of parameters as long as you use named notation when you call the program units:
SQL> SQL> declare-- from www . ja va2s. c om 2 function f_getArea_Nr(i_rad_nr NUMBER, i_prec_nr NUMBER) 3 return NUMBER 4 is 5 v_pi_nr NUMBER:=3.14; 6 begin 7 return trunc(v_pi_nr * (i_rad_nr ** 2),i_prec_nr); 8 end; 9 function f_getArea_Nr(i_length_nr NUMBER, i_width_nr NUMBER) 10 return NUMBER 11 is 12 begin 13 return i_length_nr * i_width_nr; 14 end; 15 begin 16 DBMS_OUTPUT.put_line('Area (R=3): '||f_getArea_Nr(i_rad_nr=>3,i_prec_nr=>1)); 17 DBMS_OUTPUT.put_line('Area (2x3): '||f_getArea_Nr(i_length_nr=>2,i_width_nr=>3)); 18 end; 19 / Area (R=3): 28.2 Area (2x3): 6 PL/SQL procedure successfully completed. SQL>