Isosyllabics is the regulation of verse lines by the number of syllables. Because English verse, unlike that in some other languages – French, Italian and Japanese for example – is timed by beats rather than syllables (see prosody), this produces only notional metre, undetectable to the ear. Isosyllabic verse begins to be prominent in English shortly after 1900 with the Modernists’ abandoning of metrical form and imitation of such verse forms as the Japanese
Groves, Peter Lewis. "Isosyllabics". The Literary Encyclopedia. First published 23 June 2004; last revised 30 November -1.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=1435, accessed 28 April 2015.]