large box with a flat lid

ARK
WordClue
CAPlid
TACKsmall nail with a flat head
BERETflat-topped cap
CHESTpacking-box, box
COVERlid
MEUSElarge river in Europe
NEMANlarge river in Europe
OCEANlarge body of saline water
PLANElevel or flat surface
PUNCHbox
RHINElarge river in Europe
WAFERthin, flat cookie
CASKETlittle box, e.g. for jewellery
TUNDRAflat and treeless Arctic biome
LASAGNAflat sheet of pasta
MAILBOXletter box
APARTMENTflat
BIRDHOUSEnesting box
SCHNITZELbreaded, fried flat piece of meat
SARCOPHAGUSbox-like funeral receptacle
OCEANlarge body of saline water
KELPlarge brown seaweed