To save this word, you'll need to log in.
black·fly | \ ˈblak-ˌflī 
\
\ plural blackflies or blackfly
Definition of blackfly
: any of various small dark-colored insects especially : any of a family (Simuliidae and especially genus Simulium) of bloodsucking dipteran flies whose larvae usually live in flowing streams
Keep scrolling for more
Keep scrolling for more
More Definitions for blackfly
blackfly
nounEnglish Language Learners Definition of blackfly
: a small fly that bites
See the full definition for blackfly in the English Language Learners Dictionary
blackfly
nounblack·fly | \ ˈblak-ˌflī \
\ plural blackflies
Medical Definition of blackfly
: any of a family (Simuliidae) and especially genus Simulium of bloodsucking dipteran flies
Comments on blackfly
What made you want to look up blackfly? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Semantic Drift Quiz
- Which of the following was once a synonym for fun?
Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
- Semantic Drift Quiz
A challenging quiz of changing words.
Take the quiz - A Thanksgiving Word Quiz
We are thankful for obscure words.
Take the quiz - Spell It
Can you spell these 10 commonly misspelled words?
Take the quiz - Dictionary Devil
The dictionary has been scrambled—can you put it back together?
Play the game
Share blackfly
Time Traveler for blackfly
The first known use of blackfly was in the 15th century
See more words from the same century