define: sacrifice

As per Ayn Rand's book Atlas Shrugged (written in my words here):
A mother who forgoes buying a hat in order to afford some milk for her baby is not making a sacrifice; simply because she is buying the milk for the baby that she values more than a hat. However, if there were a mother who thought that buying a hat is more valuable, and yet bought milk for her baby as if its her duty to do it, THAT would be a sacrifice.

In the above context, it is argued that sacrifice is not good. Her philosophy argues that we should do something only if we really want to do it; do it only because we hold its value higher than something else. And if we do something because we think its important, then we shouldnt consider it as a sacrifice of that something else.

Interesting philosophy for sure.. but it needs some more thought before mapping to our world. Firstly, we need to define what sacrifice means to us, not philosophically I mean, but realistically. What does the dictionary say sacrifice is? I googled and was amazed at the vast semantics the word "sacrifice" held! The one definition that we might all think of is, "the surrender or destruction of something prized or desirable for the sake of something considered as having a higher or more pressing claim."

There were few others definitions also like "surrendered or lost in order to gain an objective" and "a loss entailed by giving up or selling something at less than its value". Observe that the former talks of gaining an objective while the latter talks of ending on a loss! I just realized that I had no idea what the word sacrifice meant, or rather that never before had I actually given this word any serious consideration...