from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of or belonging to the series of elements whose atomic numbers are greater than 103.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Lying beyond actinium in the periodic table; having an atomic number greater than 103.
- n. Any of the artificially produced elements having an atomic number greater than 103.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. of or belonging to the elements with atomic numbers greater than 103
- n. any of the artificially produced elements with atomic numbers greater than 103
trans- + actinide (Wiktionary)