“Sewall”

We have one entry that includes the term Sewall.

Sewall Wright effect

noun

: differentiation within a group arising from chance fixation of nonadaptive characters in small isolated populations

See the full definition

Word of the Day

Listen to the pronunciation of collaborate

See Definitions and Examples »

Test Your Vocabulary

Challenging Standardized Test Words, Vol. 2

  • a pencil broken in half on top of a test answer sheet
  • The business’s new computer system proved not to be a panacea.
Spell It

Hear a word and type it out. How many can you get right?

TAKE THE QUIZ
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.

Pick the best words!

PLAY
Love words? Need even more definitions?

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

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
a game of hangman on lined paper
Hangman Lightning Round Figure out which word fits in the blanks.
See All