Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «M»:
Male chromosome: See: Y chromosome....
Male chromosome complement
Male chromosome complement: The large majority of males
have a 46, XY chromosome complement (46 chromosomes including an X and a Y chromosome). A
minority of males have other chromosome constitutions such as 47,XXY (47 chromosomes
including two X chromosomes and a Y chromosome) and 47,XYY (47 chromo...
Male condom: The male condom is a sheath placed over the erect penis before penetration, preventing pregnancy by blocking the passage of sperm. It is a barrier method of contraception.
A condom can be used only once.
Although some condoms have spermicide added (the spermicide is usually nonoxynol-9 ...
Male external genitalia
Male external genitalia: The external genital structures of the male, comprising the penis, the male urethra, and the scrotum....
Male genitalia: The genital organs of the male. These are usually separated by convention into the external and internal genitalia.
The male external genitalia comprise the penis, the male urethra, and the scrotum.
The male internal genitalia comprise the testis, epididymis, vas deferens, seminal ...
Male gonad: The male gonad, the testicle (or testis), located behind the penis in a pouch of skin (the scrotum). The testicles produce and store
sperm, and they are also the body's main source of male hormones (testosterone). These hormones control the development of the reproductive organs and oth...
Male internal genitalia
Male internal genitalia: The internal genital structures of
the male that are concerned with reproduction, including the testis, epididymis, vas deferens, seminal vesicle, ejaculatory duct, bulbourethral gland, and the prostate....
Male menopause: A controversial concept reflecting the belief that the decline in testosterone levels observed in men as they age causes a clinically significant and potentially treatable set of symptoms, including sexual dysfunction, mood changes, weight gain, fatigue, and other nonspecific symptom...
Male organs of reproduction
Male organs of reproduction: The sum total of all the male genital organs, both internal and external, that are concerned with reproduction, including:
The male external genitalia -- the penis, the male urethra, and the scrotum; and
The male internal genitalia -- the testis, epididymis, ductus d...
Male pelvis: The lower part of the abdomen located between
the hip bones in the male. There are significant differences in the anatomy of the pelvis in the female and male. The male pelvis is more robust, narrower, and taller than the female pelvis. The angle of the male pubic arch and the sacrum a...
Male sexual orientation gene
Male sexual orientation gene: See: Gay gene....
Malformation: A structural defect in the body due to abnormal embryonic or fetal development. There are many types of malformations. For example, cleft lip and cleft palate. See also Congenital malformation....
Malformation, arteriovenous: An arteriovenous malformation (AVM) is a congenital disorder (one present at birth) of blood vessels in the brain, brainstem, or spinal cord that is characterized by a complex, tangled web of abnormal arteries and veins connected by one or more fistulas (abnormal communi...
Malformation, arteriovenous (AVM)
Malformation, arteriovenous (AVM): An arteriovenous malformation (AVM) is a congenital disorder (one present at birth) of blood vessels in the brain, brainstem, or spinal cord that is characterized by a complex, tangled web of abnormal arteries and veins connected by one or more fistulas (abnormal c...
Malformation, congenital: A physical defect present in a baby at birth, irrespective of whether the defect is caused by a genetic factor or by prenatal events that are not genetic. In a malformation, the development of a structure is arrested, delayed, or misdirected early in embryonic life and the...