M meaning in Jobs ?

A man is an adult male human. Prior to adulthood, a male human is referred to as a boy (a male child or adolescent).

Like most other male mammals, a man's genome usually inherits an X chromosome from the mother and a Y chromosome from the father. The male fetus produces larger amounts of androgens and smaller amounts of estrogens than a female fetus. This difference in the relative amounts of these sex steroids is responsible for the physiological differences that distinguish men from women. During puberty, hormones which stimulate androgen production result in the development of secondary sexual characteristics, thus exhibiting greater differences between the sexes. These include greater muscle mass, the growth of facial hair and a lower body fat composition.

Male anatomy is distinguished from female anatomy by the male reproductive system, which includes the penis, testicles, sperm duct, prostate gland and the epididymis, as well as seconday sex characteristics.

There are exceptions to the above in regards to transgender and intersex men.