1. To warn or give notice beforehand.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• foroward,
• forelorn,
• forrward,
• foreward,
• forwarn,
• foraward,
• fireware,
• forewer,
• foresworn,
• forewore,
• doreteree,
• foredeisgn,
• forerawn,
• forswart,
• Foresward,
• foreware,
• forewarnd,
• forewarne,
• dorewarn,
• corewarn

• forewarning,
• forearm.

The adverb form of "forewarn" is "forewarnedly".

The adjective form of the word "forewarn" is "forewarning".

The plural form of the word "forewarn" is not commonly used, as it is usually used in its singular form as a verb. However, if it were to be used in the plural form, it would be "forewarns"

The singular form of the word "Forewarn" is "Forewarning"