onium

As nouns the difference between onium and odium

is that onium is any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families while odium is hatred; dislike.

As a noun onium

is (chemistry) any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families or onium can be (physics) the bound pair of a particle and its antiparticle.

As a proper noun conium is

.

As nouns the difference between onium and opium

is that onium is any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families while opium is a yellow-brown, addictive narcotic drug obtained from the dried juice of unripe pods of the opium poppy, Papaver somniferum, and containing alkaloids such as morphine, codeine, and papaverine.

As nouns the difference between onium and ionium

is that onium is (chemistry) any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families or onium can be (physics) the bound pair of a particle and its antiparticle while ionium is (physics|dated) a supposed decomposition-product of actinium once thought to be the source of radium.

As nouns the difference between onium and omnium

is that onium is (chemistry) any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families or onium can be (physics) the bound pair of a particle and its antiparticle while omnium is (cycling) a multiple race event in track cycling historically the omnium has had a variety of formats currently it consists of the following six events: flying lap, points race, elimination, individual pursuit, scratch race, and time trial.