A platform or level ground surface on which heavy guns are mounted.
[French terreplein, from Italian terrapieno, from terrapienare, to fill with earth : terra, earth (from Latin; see ters- in the Appendix of Indo-European roots) + pieno, full (from Latin plēnus; see pelə-1 in the Appendix of Indo-European roots).]
(click for a larger image)terreplein
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