Answer:

HALEST

Answer	Crossword Clue
HALEST	Heartier than the rest
HALEST	Most sound
HALEST	Most fit

HALEST	Least frail
HALEST	Most healthy
HALEST	In the best shape
HALEST	Most strapping
HALEST	Least sickly
HALEST	Most robust
HALEST	Least infirm
HALEST	Most sound.

HALEST	Most vigorous.
HALEST	Healthiest.
HALEST	In the best of health.
HALEST	Soundest.
HALEST	Healthiest
HALEST	Most hearty
HALEST	Most vigorous
HALEST	In the best of health

HALEST	Superlatively sound

Crossword

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