R star
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R star
[′är ‚stär] (astronomy)
A star of spectral type R, having spectral characteristics similar to those of types G and K, except that molecular bands of molecular carbon (C2), cyanogen radical (CN), and methyldadyne (CH) are prominent.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.