What is the meaning of Duckboard?

One of a long series of boards laid from side to side as a path across wet or muddy ground; normally used in plural.

Wooden, low walkway or short part of a path with one or more planks, logs, or boards laid after each other lengthwise, often two planks wide; also called bog board, bog bridge, or puncheon.

A panel of wooden slats typically lain on a concrete floor in a workshop. Compliance of slats arranged in two crossed layers reduces fatigue for a person operating a machine tool or working at a bench.

C. E. W. Bean (1917) Letters from France, Cassell and Company, pages 38–39:I have said before that you do not walk on the bottom of the trench as you did in Gallipoli, but on a narrow wooden causeway not unlike the bridge on which ducks wander down from the henhouse to the yard—colloquially known as the “duck-boards.

Source: wiktionary.org