hahnium

[ hah-nee-uh m ]
/ ˈhɑ ni əm /

noun Chemistry, Physics.

a proposed name for dubnium. Symbol: Ha
Also called unnilpentium, element 105.

Origin of hahnium

1965–70; after German chemist O. Hahn; see -ium

Definition for hahnium (2 of 4)

unnilpentium
[ yoo-nil-pen-tee-uh m ]
/ ˌyu nɪlˈpɛn ti əm /

noun Chemistry, Physics.

a former name of dubnium. Symbol: Unp
Also called element 105. Formerly hahnium.

Origin of unnilpentium

1975–80; < Latin ūn(us) one + nīl nothing + Greek pént(e) five + New Latin -ium -ium

Definition for hahnium (3 of 4)

dubnium
[ doob-nee-uh m, duhb- ]
/ ˈdub ni əm, ˈdʌb- /

noun Chemistry, Physics.

a superheavy, synthetic, radioactive element with a very short half-life. Symbol: Db; atomic number: 105.
Formerly hahnium, unnilpentium, element 105.

Origin of dubnium

named after Dubna, the town in Russia where it was first produced; see -ium

Definition for hahnium (4 of 4)

element 105

noun Chemistry, Physics.

Formerly unnilpentium, hahnium.

Origin of element 105

First recorded in 1975–80

British Dictionary definitions for hahnium (1 of 2)

hahnium
/ (ˈhɑːnɪəm) /

noun

a name once advanced by the American Chemical Society for a transuranic element, artificially produced from californium, atomic no: 105; half-life of most stable isotope, 262 Ha: 40 seconds Now called dubnium

Word Origin for hahnium

C20: named after Otto Hahn

British Dictionary definitions for hahnium (2 of 2)

dubnium
/ (ˈdʌbnɪəm) /

noun

a synthetic transactinide element produced in minute quantities by bombarding plutonium with high-energy neon ions. Symbol: Du; atomic no 105 See hahnium

Word Origin for dubnium

C20: after Dubna, where it was first reported

Scientific definitions for hahnium

dubnium
[ dōōbnē-əm ]

Db

A synthetic, radioactive element that is produced from californium, americium, or berkelium. Its most long-lived isotopes have mass numbers of 258, 261, 262, and 263 with half-lives of 4.2, 1.8. 34, and 30 seconds, respectively. Atomic number 105. See Periodic Table.