'"Ballon d'essai" is the French equivalent of this, sent up to test people's reaction'
trial balloon
IDIOMS: Ballon dessai is the French equivalent of this, sent up to test peoples reaction
"Ballon d'essai" is the French equivalent of this, sent up to test people's reaction
"Ballon d'essai" is the French equivalent of this, sent up to test people's reaction
IDIOMS
trial balloon
IDIOMS