From the given options choose the one which is opposite in meaning to the word given below 

AHEAD

Behind

The word that is opposite in meaning to ahead is behind.

• Ahead means in front of or in advance of something else.
• Behind means in the rear or back of something else.

The other options are not opposites of ahead.

• Forward means moving or facing in the direction of progress or advancement.
• Above means higher than something else.
• Infront means in front of or facing something else.