To be committed is to be "all in", no excuses, no back door. The phrase that goes along with it is "no matter what".
Click through and see the story of the chicken and the pig and understand what true commitment looks like.
Many of us go through our lives without true commitment to what we are doing and our lives are smaller an poorer as a result. Being committed means finding something that inspires us sufficiently that we will go all in to get it. No escape routes, no way to back down, death or glory. That is how you live a big life and know that at the end you have given everything you had regardless of the outcome.