The term "tailwinds" describes some condition or situation that will help move growth higher. For example, falling gas prices will help a delivery company be more profitable. Lower gas prices is said to be a tailwind for the freight services industry.
"Headwinds" are just the opposite. Its a situation what will make growth more difficult. IfFor example, if the price of beef goes much highhigher, McDonald's is facing headwinds.
It's a nautical term. If the wind is at your back (tailwind), that will help you move forward more quickly. If you are moving into a headwind, that will only make progress more difficult.