When euphemism is mentioned, it is thought to be merely taught as one of the literary terms. However, for those that don't even love literature, it forms part of their daily conversation.

The term euphemism refers to polite, indirect expressions which replace words and phrases considered harsh and impolite or which suggest something unpleasant. In other words, any word or expression intended to avoid being harsh, disrepectful or offensive is euphemism.

Why euphemism? Euphemisms can be conventional. That is, they are generally acceptable based on norms, cultural practices and beliefs in a given society. Writers or speakers can also deliberately choose to use euphemism to avoid embarrassing a portion of their audience. When this is the case, the context must be understood to unravel the intended meaning of the writer or speaker's use of euphemism.

Functions of Euphemism
1. Euphemism helps writers to convey those ideas which have become a social taboo and are too embarrassing to mention directly.

2. Writers skillfully choose appropriate words to refer to and discuss a subject indirectly which otherwise are not published due to strict social censorship e.g. religious fanaticism, political theories, sexuality, death etc.

3. Euphemism is a useful tool that allows writers to write figuratively about the libelous issues. (These functions were gleaned from online sources)

Euphemisms are employed in various forms.

1. They may be in form of abbreviations. Examples include:
BO (body odour)
WC (water closet)
PLHA (People Living With HIV)
IDPs (Internally Displaced Persons)
LGBT (Lesbian, Gay, Bisexual, and Transgender)
CD (condom)

2. Substitution of impolite words or phrases for polite ones.
...My uncle forced himself into the secrecy of my being (to imply being raped)

[He] patted women's rears (to imply touching women's buttocks)

Punctually challenged (to imply late-comers)

Commercial sex workers (to imply prostitutes)

Special children/children with special needs (to imply children with disabilities)

Visually impaired (to imply people who are blind)

Carnal knowledge (to imply illicit sexual intercourse)

Mentally challenged (to imply people with mental problems)

Restrooms—gents and ladies (to imply toilets)

Downsizing (to imply mass sacking)

Adult beverages (to imply alcohol or alcoholic drinks)

Adult movies (to imply pornography)

Ethnic cleansing (to imply mass killing of an ethnic group)

He has a rare attribute of managing the truth (to imply lying)

He has an unusual affinity for truth management (to imply lying)

Accidental discharge (to imply shooting by mistake)

Domestic staff (to imply workers like drivers, cooks, cleaners, etc)

3. Coinages or semantic extensions (i.e. a word is forced to take up another meaning)
404 (to imply dog meat)

Round about (used by patrons of food vendors to imply an inner part a bull or goat meat)

The Lord is my barber (to reference a bald man)

4. Deliberately replacing certain words for another
Rather than say, Haye is fat or obese (which can be embarrassing to mean Haye has excessive body fat), you can say, Haye is robust.
Rather than say, Kunle is thin (which can be embarrassing to mean Kunle is malnourished), you can say, Kunle is slim.

Euphemisms are diversely used in the Bible too. Examples include:
And he [Saul] came to...where there was a cave; and Saul went in to cover his feet. (I Sam. 24:3)

...Adam knew Eve his wife. (Gen. 4:1)

...Abimelech...looked out of a window, and saw [that] Isaac was sporting with Rebekah his wife. (Gen. 26:

David called one of the young men, and said, Go near, and fall upon him. (2 Sam. 1:15)

When he [Onan] went in unto his brother's wife,...he spilled it on the ground. (Gen. 38:9)

We take some examples in Yoruba.
A witty definition of euphemism in Yourba is expressed in the expression, a kin fi gbogbo enu soro (meaning, rather than being excessively vocal, one can spare certain details)

Awon too wo ju Oluwa (to imply those who are barren)
O n fe wo/o n se afowora (to imply someone steals)
O ti se alaisi (to imply someone is dead)
Oba ti waja (to imply the king is dead)
Nnkan omo kurin/nnkan omo birin (to imply male and female genitals)
Owo po lowo mi (to imply someone is not financially buoyant)

Source: http://olabanjititles..com.ng