word forming element indicating "oneself," also "automatic," from Old English use of self (pron.) in compounds, such as selfbana "suicide," selflice "self-love, pride, vanity, egotism," selfwill "free will."
late 13c., "offering of something (especially a life) to a deity as an act of propitiation or homage;" mid-14c., "that which is offered in sacrifice," from Old French sacrifise "sacrifice, offering" (12c.), from Latin sacrificium, from sacrificus "performing priestly functions or sacrifices," from sacra "sacred rites" (properly neuter plural of sacer "sacred;" see sacred) + combining form of facere "to make, to do" (from PIE root *dhe- "to set, put").
Latin sacrificium is glossed in Old English by ansegdniss. Sense of "act of giving up one thing for another; something given up for the sake of another" is first recorded 1590s. Baseball sense first attested 1880.
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Definitions of self-sacrifice from WordNet
acting with less concern for yourself than for the success of the joint activity;