Ein or EIN may refer to:

Science and technology

Ein function In mathematics, the exponential integral Ei is a special function on the complex plane. It is defined as one particular definite integral of the ratio between an exponential function and its argument of a function, argument. Definitions For real ...

, in mathematics *

Endometrial intraepithelial neoplasia Endometrial intraepithelial neoplasia (EIN) is a premalignant lesion of the uterine lining that predisposes to endometrioid endometrial adenocarcinoma. It is composed of a collection of abnormal endometrial cells, arising from the glands that li ...

, a lesion of the uterine lining *

Equivalent input noise Equivalent input (also input-referred, referred-to-input (RTI), or input-related), is a method of referring to the signal or noise level at the output of a system as if it were due to an input to the same system. This input's value is called the ...

, of a microphone *

European Informatics Network In telecommunications, packet switching is a method of grouping data into short messages in fixed format, i.e. '' packets,'' that are transmitted over a digital network. Packets consist of a header and a payload. Data in the header is used b ...

, a 1970s computer network

Fictional characters

* Ein, a character in the anime series ''Cowboy Bebop'' * Ein, a character in the video game series ''Dead or Alive'' * Ein, the protagonist of the Game Boy Advance game '' Riviera: The Promised Land''

Other uses

Aer Lingus Aer Lingus ( ; an anglicisation of the Irish language, Irish , meaning "air fleet") is an Irish airline company which is the flag carrier of Republic of Ireland, Ireland. Founded by the Irish Government, it was privatised between 2006 and 201 ...

(ICAO code), the flag carrier airline of Ireland *

Eindhoven Airport Eindhoven Airport is an international airport located west of Eindhoven, Netherlands. In terms of the number of served passengers, it is the second largest airport in the Netherlands, with 6.8 million passengers in 2023. The airport is used by ...

(IATA code), in the Netherlands *

Employer Identification Number The Employer Identification Number (EIN), also known as the Federal Employer Identification Number (FEIN) or the Federal Tax Identification Number (FTIN), is a unique nine-digit number assigned by the Internal Revenue Service (IRS) to business enti ...

, assigned by the US Internal Revenue Service *

EPODE International Network EPODE International Network (EIN) is a not for profit, non-governmental organisation that seeks to support childhood obesity-prevention programmes across the world. The name EPODE comes from ‘Ensemble Prévenons l'ObésitéDes Enfants’ Toge ...

, a Belgian obesity organization {{disambiguation, surname