The words featured in this post have a word in common: the Latin adjective sacer, meaning “holy.”
The word’s direct descendant is sacred. Other terms include sacrament, which describes a religious observance or rite, and sacerdotal, which refers to things that pertain to a priest or the priesthood. A sacristy is a room where sacred objects are kept and where priests dress for services; a sacristan is a person in charge of the room and its contents. (Sexton, by way of the Anglo-French segrestein, is derived from the same Latin precursor as sacristan but refers more broadly to a church caretaker.)
Sacrilege originally referred to stealing something sacred but later came to refer as well to any seriously irreverent act, although it is sometimes used to facetiously allude to something that merely mocks convention or tradition; the adjectival form is sacrilegious (which, despite looking and sounding similar to religious, is unrelated to that word).
Sacrifice, from the Latin words sacra (“holy rites”) and facere (“perform”), originally meant just that but later referred to killing someone or something as an offering to a deity. In use as both a noun and a verb, it also applies in nonreligious contexts to destroying something or giving it up. In baseball, a sacrifice fly or hit occurs when a batter accidentally or deliberately hits the ball and is called or forced out but by doing so enables a teammate already on base to advance.
To consecrate is to devote, or make holy; an act of doing so is consecration. To desecrate is to damage or destroy something sacred; desecration is such an act. To execrate, by contrast, is to curse, and the noun is execration. The adjective execrable originally meant “fit to be cursed,” but the modern sense is of something detestable or wretched. The rare term obsecration means “beseech” or “implore” (and is unrelated to the noun obsequy, meaning “funeral rites,” and the adjective obsequious, which means “overly compliant”).
The anatomical term sacrum and its adjectival form sacral, both referring to the bone at the base of the spine, originate from the Latin term os sacrum (“sacred bone”). Competing theories for the significance of the term are that the part of the body in which it is located was used in sacrifices and that because the Greek term from which os sacrum is derived is hieron osteon, and hieron also means “strong,” the meaning is “strong bone.” (In anthropology, the adjectival form means “pertaining to religious rites.”)