0 Old HSK word(s):
陆海空* *

Definitions from Unihan Copyright © 1991-2015 Unicode® Inc. All rights reserved.

陆 land, continental / army
海 sea, ocean / maritime
空 empty, hollow, bare, deserted

Hsk Characters:
HSK -Characters and beyond:
GbBig5EngRadMegaTripleMultilingual