There's a concise "full definition" of the secular meaning of sacrifice at the Merriam & Webster site:
"3 a: destruction or surrender of something for the sake of something else"
It's different than what Ayn Rand thought the word meant:
“Sacrifice” is the surrender of a greater value for the sake of a lesser one or of a nonvalue.
Note that Rand's version would be a subset of Merriam Webster's version.
Natural languages are messy, of course. Rand may have been onto something when it came to the word's mid 20th century connotation. But it's clear that a "sacrifice fly" in baseball has nothing to do with Rand's definition, while it fits neatly in Merriam Webster's. I don't wish to put too much importance on baseball idiom, but I think it's clear you could pile up such examples, where sacrifice merely indicates painful but beneficial prioritization.
Of course, Rand was an atheist, so the background metaphor of sacrifice - destroying something to please a divine being - may have predisposed her towards the "nonvalue" definition.
If you don't believe in a god
you may indeed find it odd
that valuable things get burned
with nothing apparent returned.