Source: Standard literature
Dẹla or "net" is the Sinhalese term for a decorative motif that consists of a mesh of lines resembling a net.1
Dẹla lacquer work decoration on a Sinhalese cane.
Sold by Mandarin Mansion in 2020.
The spine of a Sinhalese knife, decorated with dẹla.
Listed at Mandarin Mansion.
The "netting" on the knife above is done with lozenges, each with an engraving in the center. Coomaraswamy suggests these are either stylized feathers or pineapple skin.2
Article: Sinhalese lacquer work
1. See Ananda K. Coomaraswamy; Medieaval Sinhalese Art, Pantheon Books, New York, Second Edition of the 1908 original, 1956. Pages 216-217.