Many examples of what Pound called "Amygism" have permeated reference sources; besides the Britannica, they may be found in entries on "cadence" and "free verse" in the Merriam-Webster and Random House dictionaries, and under "Free Verse" in the venerable Thrall and Hibbard Handbook to Literature. These definitions continue to give the impression that free verse had a metric of its own, quite independent of accentual-syllabic prosody.
Source: wiktionary