Crossword clues for the word: RRNA The word RRNA has appeared as an answer to at least 3 crossword clues on different crossword puzzles. Crossword clues for RRNA Showing 1 to 3 of 3 results Clue(s) "Cell stuff that fabricates protein, for short" AP biology subj. Molecule key for studying evolutionary relationships between species: Abbr.