I would not be able to explain to you what exactly it means as many professionals themselves rarely understand some of these terms from other closely related terms......In general/casual words it would mean that you are not having emotions to the degree that you are supposed to have i.e the amplitude of the emotional reaction to persons/events/relations is very much less than normally expected. Hope I have not confused you more! One word of caution though on Internet and self diagnosis....... believe me, diagnosis is definitely not just about ticking a check list of criteria. You can probably tick weather you have some biological symptoms like lack of appetite, disturbed sleep etc but when it comes to qualitative symptoms like anhedonia, blunted affect, tangential thinking etc etc etc.....you better leave these to professionals. Experience does count for something, in every profession. Hope you take my answer in the right spirit. Good Luck