Answer:

threshold

Answer	Crossword Clue
THRESHOLD	Entrance demarcation
THRESHOLD	Beginning point.
THRESHOLD	Sill.

THRESHOLD	Point of entry
THRESHOLD	... Test-Ban Treaty: 1974
THRESHOLD	Starting point
THRESHOLD	Doorsill

Crossword

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