The Collaborative International Dictionary of English v.0.48:

Lepidodendrales \Lepidodendrales\ n.
   An order of fossil arborescent plants arising during the
   Lower Devonian and conspicuous throughout the Carboniferous.

   Syn: order Lepidodendrales.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Lepidodendrales
    n 1: fossil arborescent plants arising during the early Devonian
         and conspicuous throughout the Carboniferous [syn:
         Lepidodendrales, order Lepidodendrales]