masto-

1. a combining form meaning “breast,” used in the formation of compound words.

   mastopathy.

masto-

combining form

1. indicating the breast, mammary glands, or something resembling a breast or nipple

   mastodon

   mastoid

Word History and Origins

Origin of masto-¹

Combining form representing Greek mastós breast

Word History and Origins

Origin of masto-¹

from Greek mastos breast

Example Sentences

Cortez Masto, a former state attorney general, was first elected to the Senate in 2016, replacing the onetime Senate majority leader, Harry Reid, after the Democrat retired.

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Six years later, when she sought reelection, Cortez Masto was widely considered Democrats’ most endangered incumbent.

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Cortez Masto next faces reelection in 2028, which is politically ages away.

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Cortez Masto noted, dryly, that Congress is, in fact, a separate branch of government with its own power and authority.

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“We’ve got to govern,” Cortez Masto said.

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When To Use

What does masto- mean?

Masto- is a combining form used like a prefix meaning “breast.” It is often used in medical terms, especially in anatomy and pathology.Masto- comes from the Greek mastós, meaning “breast.” The Latin-based analog to masto- is mammo-, from mamma, meaning “breast.”What are variants of masto-?When combined with words or word elements that begin with a vowel, masto- becomes mast-, as in mastectomy.