E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The alphabet in use among the ancient Irish and some other Celtic nations prior to the ninth century.
The oghams seem to have been merely treerunes. The Irish regarded the oghams as a forest, the individual characters being trees (feada), while each cross-stroke is called a twig (fleasg).Isaac Taylor: The Alphabet, vol. ii. chap. viii. p. 226.