Answer:

waterline

Answer	Crossword Clue
WATERLINE	Floating point
WATERLINE	Hull mark
WATERLINE	Tide mark

WATERLINE	Plimsoll mark.
WATERLINE	Flood mark
WATERLINE	Ship marking
WATERLINE	Bank limit?

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.