Some learned scholar has given a very interesting definition of taqwa and has explained it with an interesting example too.

When you walk barefooted through a thorny jungle, how will you traverse the way? Will you keep your eyes up and walk casually or keep every step with due care and observation to prevent the thorns hurting your bare feet?

Taqwa too means that on the path of life Satan has spread thorns and the man of piety has to save himself from getting hurt by them and keep moving forward all the time.