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molly

1 American  
[mol-ee] / ˈmɒl i /

noun

PLURAL

mollies
  1. any of certain livebearing freshwater fishes of the genus Poecilia (formerlyMollienisia ), popular in home aquariums.


molly 2 American  
[mol-ee] / ˈmɒl i /

noun

PLURAL

mollies
  1. a type of expansion bolt having a split, sleevelike sheath threaded at one end so that when inserted snugly into masonry the turning of the bolt draws the ends of the sheath together, thus spreading the sides.


molly 3 American  
[mol-ee] / ˈmɒl i /

noun

Slang.
  1. Often Molly MDMA.

  2. any amphetamine.


molly 4 American  
[mol-ee myool] / ˈmɒl i ˌmyul /

noun

  1. a female mule.


Molly 5 American  
[mol-ee] / ˈmɒl i /

noun

  1. a female given name, form of Mary or Milicent.


molly 1 British  
/ ˈmɒlɪ /

noun

  1. any brightly coloured tropical or subtropical American freshwater cyprinodont fish of the genus Mollienisia

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

molly 2 British  
/ ˈmɒlɪ /

noun

  1. informal  an effeminate, weak, or cowardly boy or man

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of molly1

First recorded in 1930–35; shortened from New Latin Mollienisia, named after French statesman Count F. N. Mollien (1758–1850); -ia

Origin of molly2

First recorded in 1930–35; formerly a trademark

Origin of molly3

First recorded in 1975–80; origin uncertain; perhaps a shortening of black molly, a tropical aquarium fish supposedly resembling the black pills; other authorities suggest it is a shortening and alteration of molecule ( def. )

Origin of molly4

First recorded in 1980–85; generic use of the proper name

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

I founded molly moon’s with the mission of making the world a better place, one scoop at a time.

From Seattle Times

She just had some questions how to treat ich, an illness that had wiped out her mollies.

From New York Times

He winds up there because of a “hustle,” as he describes it, which involved selling his classmates what they believed to be coke or molly but was actually Sudafed ground with sea salt.

From New York Times

Small freshwater fish called sulfur mollies synchronously splash their tails to create waves, and scientists have now demonstrated that this strategy can deter hungry birds.

From Scientific American

The mollies are prey for an array of winged predators, including egrets, kingfishers and kiskadees.

From Seattle Times