Dorky describes a person, a look, or a thing that strikes you as awkward, unfashionable, or sweetly silly — glasses that are too big, a joke that tries too hard, a dance that is not cool. It is the adjective that belongs with dork: dork names the person, dorky names the quality. Same informal American tone. You can say “a dorky shirt” or “He looks dorky in that hat.” Young people use it a lot. It can be unkind or fond, depending on the voice. It is not a word for a formal letter. Though actually, people now stick it on objects and habits, not only on people: a dorky hobby, a dorky ringtone. That stretch is common and natural. It still sits in casual speech.