di- 1
pref.1. Two; twice; double: dichromatic.
2. Containing two atoms, radicals, or groups: dichloride.
di- 2
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
di-
prefix 1. twice; two; double: dicotyledon.
2. (Chemistry)
a. containing two specified atoms or groups of atoms: dimethyl ether; carbon dioxide.
b. a nontechnical equivalent of
bi-15c [via Latin from Greek, from dis twice, double, related to duo two. Compare bi-1]
di-
combining form variant of
dia-:
diopter.
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
DI
drill instructor.
Di
Chem. Symbol. didymium.
di-1
, a combining form meaning “two,” “double”:
diamide; dicotyledon; dihedron. Compare
dis- 2. [< Greek, comb. form representing
dís twice, double, akin to
dýo two. compare
bi-
1,
twi-]
di-2
, var. of
dis- 1 before
b, d, l, m, n, r, s, v, and sometimes
g and
j: digest; divide. di-3
, var. of
dia- before a vowel:
diorama. di.
diameter.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
di-
A prefix that means "two," "twice," or "double." It is used commonly in chemistry, as in dioxide, a compound having two oxygen atoms.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.