Sacrifice

What exactly a "Sacrifice" means?

Is this something you give up for some body just because you love the more and you want them to be happy?

Tell me is that really what "you" do, when you say 'I sacrificed "something" for you', just to see you happy.

I see in such way that, you love that person and you want them to be happy, there is your 'self interest', you are not giving up some thing for others, you are making your self happy by giving it to others.

As per dictionary also it reflects the same thing

"an act of giving up something valued for the sake of something else regarded as more important or worthy'

i.e.

"sacrifice is nothing but satisfying yourself by giving up something to get something else"

Because of our films, we say and feel too high about "sacrifice" ...