mast

Mast- is a combining form used like a prefix meaning “breast.” It is often used in medical terms, especially in anatomy and pathology.

Mast- comes from the Greek mastós, meaning “breast.” The Latin-based analog to masto- is mammo-, from mamma, meaning “breast.”

Mast- is a variant of masto-, which loses its -o– when combined with words or word elements beginning with vowels.

Want to know more? Read our Words That Use masto- article.

You may be familiar with the medical term mastectomy, “the operation of removing all or part of the breast or mamma.” The first part of the word, mast- means “breast,” as we’ve seen.  The second part of the word, -ectomy, is a combining form meaning “excision.” Mastectomy literally translates to “breast removal.”

What are some words that use or are related to the combining form mast-?

• mastadenoma
• mastalgia
• mastatrophy
• mastitis
• mastodynia
• mastoid (using the equivalent form of masto- in Greek)
• mastoiditis (based on mastoid)

What are some other forms that mast- may be commonly confused with?

• -masted
• met-
• mes-
• mis-

The mast on a ship is unrelated to the combining form mast-, as are a number of other words that begin with the letters mast-, such as masticate. Chew over the origin of this word at our entry for it.

Also note that mast cells, from the German Mast (“fattening of animals for slaughter”), are not related to masto-. These cells give their name to such conditions as mastocytosis.

The combining form –algia means “pain.” What is mastalgia?