Virility
Virility (from the Latin virilitas, manhood or virility, derived from Latin vir, man) refers to any of a wide range of masculine characteristics viewed positively. It is applicable to women and not to negative characteristics. The Oxford English Dictionary (OED1) says virile is "marked by strength or force". Virility is commonly associated with vigour, health, sturdiness, and constitution, especially in the fathering of children. In this last sense, virility is to men as fertility is to women. OED1 also notes that virile has become obsolete in referring to a "nubile" young woman, or "a maid that is Marriageable or ripe for a Husband, or Virill".
Historically, masculine attributes such as beard growth have been seen as signs of virility and leadership (for example in ancient Egypt and Greece).
Male virility
Evidence shows that increased male age is associated with a decline in semen volume, sperm motility, and sperm morphology. In studies that controlled for female age, comparisons between men under 30 and men over 50 found relative decreases in pregnancy rates between 23% and 38%.