variants or less commonly poly I·poly C
: a synthetic 2-stranded RNA that induces interferon formation and is composed of one strand consisting entirely of cytosine-containing nucleotides and one strand consisting entirely of inosine-containing nucleotides

Word History


poly- + inosinic acid + cytidylic acid

First Known Use

1969, in the meaning defined above

Time Traveler
The first known use of poly I:C was in 1969

Dictionary Entries Near poly I:C

Cite this Entry

“Poly I:C.” Dictionary, Merriam-Webster, Accessed 26 Mar. 2023.

Medical Definition

poly I:C

: a synthetic 2-stranded RNA composed of one strand of polyinosinic acid and one strand of polycytidylic acid that induces interferon formation and has been used experimentally as an anticancer and antiviral agent

called also poly I·poly C

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