Answer:

serous

Answer	Crossword Clue
SEROUS	Pertaining to blood fluid
SEROUS	Watery
SEROUS	Like an antitoxin

SEROUS	Like blood fluid
SEROUS	Of a watery nature.
SEROUS	Thin; watery.
SEROUS	Thin and watery.
SEROUS	Thin and watery

Crossword

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