Bi
Multiple Entries:Bi bi bi- bismuth
Concise Oxford English Dictionary © 2008 Oxford University Press:
Bi
▶symbol the chemical element bismuth.
Concise Oxford English Dictionary © 2008 Oxford University Press:
bi /bʌɪ/
▶abbreviation informal bisexual.
Concise Oxford English Dictionary © 2008 Oxford University Press:
bi- /bʌɪ/ (also bin- before a vowel)
▶combining form two; having two: biathlon.
■ occurring twice in every one or once in every two: bicentennial.
■ lasting for two: biennial.
■ Chemistry (in names of compounds) containing two atoms or groups of a specified kind: biphenyl.
■ Chemistry denoting an acid salt: bicarbonate.
– origin from L., ‘doubly, having two’; rel. to Gk di- ‘two’.
usage: The meaning of bimonthly (and similar words such as biyearly) is ambiguous. Such words can either mean ‘occurring or produced twice a month’ or ‘occurring or produced every two months’. The only way to avoid this ambiguity is to use alternative expressions like every two months and twice a month.
Concise Oxford English Dictionary © 2008 Oxford University Press:
bismuth /ˈbɪzməθ/
▶noun the chemical element of atomic number 83, a brittle reddish-tinged grey metal. (Symbol: Bi)
– origin C17: from mod. L. bisemutum, Latinization of Ger. Wismut, of unknown origin.
'Bi' also found in these Oxford entries:

