"explosive projectile," originally consisting of a hollow ball or shell filled with explosive material, 1580s, from French bombe, from Italian bomba, probably from Latin bombus "a deep, hollow noise; a buzzing or booming sound," from Greek bombos "deep and hollow sound," echoic. Thus probably so called for the sound it makes.
Originally of mortar shells, etc.; modern sense of "explosive device placed by hand or dropped from airplane" is from 1909. The meaning "old car" is from 1953. The meaning "success" is from 1954 (late 1990s slang the bomb "the best" probably is a fresh formation); opposite sense of "a failure" is from 1961. The bomb "the atomic bomb" is from 1945. Compare shell (n.).
1945, originally CARE package, supplies sent out by "Cooperative for American Remittances to Europe," established 1945 by U.S. private charities to coordinate delivery of aid packages to displaced persons in Europe after World War II and obviously named for the sake of the acronym. The name was repackaged late 1940s to "Cooperative for Assistance and Relief Everywhere," to reflect its expanded mission.
"strong enough to resist the impact and explosive force of bombs or shells striking on the outside" [Century Dictionary], 1702, from bomb (n.) + proof (n.). As a noun, "underground structure strong enough to resist the impact and explosive force of bombs," 1755. In the U.S. Civil War it was a contemptuous term for men not exposed to the dangers of war.
"bundle, burden," c. 1300, from Old French fardel "parcel, package, small pack" (13c., Modern French fardeau), diminutive of farde, which OED says is "cognate with" (others say "from") Spanish fardo "pack, bundle," which is said to be from Arabic fardah "package."