1

gamma

noun gam·ma \ ˈga-mə \

Definition of gamma

1 :the 3rd letter of the Greek alphabet — see Alphabet Table
2 :the degree of contrast of a developed photographic image or of a video image
3 :a unit of magnetic flux density equal to one nanotesla
4 :gamma ray
  • gamma counter

Recent Examples of gamma from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gamma.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of gamma

Middle English, borrowed from Latin, borrowed from Greek gȧmma, borrowed from Phoenician *gaml-, perhaps with the original sense "throwing stick"


2

gamma

adjective

Definition of gamma

1 :of, relating to, or being one of three or more closely related chemical substances
2 :third in position in the structure of an organic molecule from a particular group or atom symbol γ

Recent Examples of gamma from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gamma.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of gamma

attributive use of 1gamma



GAMMA Defined for English Language Learners

gamma

noun

Definition of gamma for English Language Learners

  • : the third letter of the Greek alphabet


Medical Dictionary

1

gamma

noun gam·ma \ ˈgam-ə \

medical Definition of gamma

1 :the third letter of the Greek alphabet symbol Γ or γ
2 :a unit of magnetic flux density equal to one nanotesla
3 :gamma ray usually used as the attributive form of gamma ray
  • gamma counter
4 :microgram 1

2

gamma

adjective
variants: or γ-

medical Definition of gamma

1 :of or relating to one of three or more closely related chemical substances
  • the gamma chain of hemoglobin
  • γ-yohimbine
used somewhat arbitrarily to specify ordinal relationship or a particular physical form and especially one that is allotropic, isomeric, or stereoisomeric (as in gamma benzene hexachloride)
2 :third in position in the structure of an organic molecule from a particular group or atom; also :occurring at or having a structure characterized by such a position
  • γ-hydroxy acids
3 of streptococci :producing no hemolysis on blood agar plates

Learn More about gamma


Seen and Heard

What made you want to look up gamma? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

to praise usually to excess

Get Word of the Day daily email!

Test Your Vocabulary

Find the Cousins

  • a-large-tree-with-many-branches
  • Which pair shares a common word ancestor?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!