di

¹

or Di

[ dee ]

preposition

1. from; of: used in Italian personal names, originally to indicate place of origin:

   Conte di Savòia.

di-

²

1. a prefix occurring in loanwords from Greek, where it meant “two,” “twice,” “double” ( diphthong ); on this model, freely used in the formation of compound words ( dicotyledon; dipolar ) and in chemical terms ( diatomic; disulfide ).

di

³

[ dee ]

noun

, Music.

1. a tone in the ascending chromatic scale between do and re.

di-

⁴

1. variant of dis- ¹ before b, d, l, m, n, r, s, v, and sometimes g and j: digest; divide.

di-

⁵

1. variant of dia- before a vowel:

   diorama.

Di

⁶

[ dahy ]

noun

1. a female given name, form of Diana.

Di

⁷

Symbol, Chemistry.

1. didymium.

DI

⁸

1. Department of the Interior.
2. drill instructor.

di.

⁹

or dia

abbreviation for

1. diameter.

DI

¹

abbreviation for

1. Defence Intelligence
2. Detective Inspector
3. Donor Insemination

di-

²

combining_form

1. variant of dia-

   diopter

di-

³

prefix

1. twice; two; double

   dicotyledon

2. 1. containing two specified atoms or groups of atoms

      dimethyl ether

      carbon dioxide

   2. a nontechnical equivalent of bi- 1

Di

⁴

the chemical symbol for

1. didymium

di–

1. A prefix that means “two,” “twice,” or “double.” It is used commonly in chemistry, as in dioxide, a compound having two oxygen atoms.

Word History and Origins

Origin of di¹

< Italian < Latin dē

Origin of di²

Middle English ≪ Latin < Greek, combining form representing dís twice, double, akin to dýo two. See bi- ¹, twi-

Origin of di³

Perhaps alteration of do ²

Word History and Origins

Origin of di¹

via Latin from Greek, from dis twice, double, related to duo two. Compare bi- ¹