To save this word, you'll need to log in.
\ ˌem-ˌī-ˌär-(ˌ)en-ˈā 
\
\Definition of miRNA
genetics
: microrna A major part of this regulation is performed by microRNAs (miRNAs), small RNA molecules encoded by the genome that are not translated into proteins; rather, they control the expression of genes.— Sebastien S. Hebert et al.
Keep scrolling for more
Keep scrolling for more
More Definitions for miRNA
miRNA
noun\ ˌem-ˌī-ˌär-ˌen-ˈā \
\Medical Definition of miRNA
: microrna MicroRNAs (miRNAs) are 20- to 22-nucleotide RNAs that regulate the function of eukaryotic messenger RNAs (mRNAs) and play important roles in development, cancer, stress responses, and viral infections.— J. Ross Buchan et al., Science, 21 Dec. 2007 Many of the noncoding RNAs, epitomized by the miRNA, have regulatory functions in normal cells. The aberrant expression of miRNA promotes tumorigenesis, metastasis, and other features of cancer.— Frank J. Slack et al., The New England Journal of Medicine, 18 Dec. 2008
Comments on miRNA
What made you want to look up miRNA? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Pass the Little Ribbons: A Pasta Word Quiz
- Match the pasta to its meaning in English: Rotelle
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
- Pass the Little Ribbons: A Pasta Word Quiz
Match the pasta with its meaning in Italian.
Take the quiz - Confusing Words—A Quiz
Test your knowledge of these commonly confused words!
Take the quiz - Spell It
Can you spell these 10 commonly misspelled words?
Take the quiz - Bee Cubed
Listen to the words and spell through all three levels.
Play the game
Share miRNA
Resources for miRNA