A penis or other testicular object that has little or no growth and/or hardness whatsoever, even when it has received exposure to sexual preferences and/or genital stimulation.
Boy: "I was tryna get up on some girl she said my game was fairly good and she let me get a feel up so i can get horny but when i whipped out on her she saw that i was just four inches long... I checked with the doctor the next day to see about this problem and he told me that i have a really bad case of retardick and he told me i had to take these (viagra) every day." Man: "Boy you really do have a retarded functioning ass dick, Retardick." (no homo just keepin it real) "And I can hardly believe that we was born on the same year cuz where I was coming up from we never had any retardicks in our family real talk."