Term:

Festoon (adj. festooned)
Definition:

A type of leaf venation in which the secondary veins do not terminate at the margin but join to form a series of prominent arches that form a submarginal nerve and, in addtion, the secondary veins possess closed loops toward their apices. Based on Hickey, 1973. For more information about leaf venation see Ellis et al, 2009.
Notes:

Festoons are common In neotropical Lecythidaceae.