a surface on which sand can be modelled into a relief map on which to demonstrate tactics
sand table in American English
noun
1.
a table with raised edges holding sand for children to play with
2. Military
a table holding a scale model of a tract of land, including trees, streams, buildings, etc., made of hardened sand, used for training in gunnery or tactics
Word origin
[1805–15]This word is first recorded in the period 1805–15. Other words that entered Englishat around the same time include: backlash, diminishing returns, platinum, polarization, soufflé