<unk>  is the complete lack of semen (not to be confused with azoospermia, the lack of sperm cells in the semen).  Naturally, it is associated with infertility.
One of the causes of<unk>  is retrograde ejaculation, which can be brought on by excessive drug use, or as a result of prostate surgery.
Aspermia
Melanonychia
Leukonychia
Paronychia
Anonychia
Myokmia
Anosmia
Chromophobia