The copulative a is the prefix

Prefix

A prefix is an affix which is placed before the root of a word. Particularly in the study of languages,a prefix is also called a preformative, because it alters the form of the words to which it is affixed.Examples of prefixes:...

 ha- or a- expressing unity in Ancient Greek

Ancient Greek

Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

, derived from Proto-Indo-European

Proto-Indo-European language

The Proto-Indo-European language is the reconstructed common ancestor of the Indo-European languages, spoken by the Proto-Indo-Europeans...

 *, cognate to English same (see also Symbel

Symbel

Symbel and sumbl are Germanic terms for "feast, banquet".Paul C. Bauschatz in 1976 suggested that the term reflects a pagan ritual which had a "great religious significance in the culture of the early Germanic people"....

).

An example is a-delphos "brother", from * literally "from the same womb" (c.f. Delphi

Delphi

Delphi is both an archaeological site and a modern town in Greece on the south-western spur of Mount Parnassus in the valley of Phocis.In Greek mythology, Delphi was the site of the Delphic oracle, the most important oracle in the classical Greek world, and a major site for the worship of the god...

)

In Proto-Greek

Proto-Greek language

The Proto-Greek language is the assumed last common ancestor of all known varieties of Greek, including Mycenaean, the classical Greek dialects , and ultimately Koine, Byzantine and modern Greek...

, s at the beginning of a word became h by debuccalization

Debuccalization

Debuccalization is a sound change in which a consonant loses its original place of articulation and becomes or . The pronunciation of a consonant as is sometimes called aspiration, but in phonetics aspiration is the burst of air accompanying a plosive...

 and syllabic

Syllabic consonant

A syllabic consonant is a consonant which either forms a syllable on its own, or is the nucleus of a syllable. The diacritic for this in the International Phonetic Alphabet is the under-stroke, ⟨⟩...

 m̥ became a, giving ha-. The initial h was sometimes lost by psilosis

Psilosis

Psilosis is the sound change in which Greek lost the consonant sound /h/ during antiquity. The term comes from the Greek psílōsis and is related to the name of the smooth breathing , the sign for the absence of initial in a word...

.

Cognate

Cognate

In linguistics, cognates are words that have a common etymological origin. This learned term derives from the Latin cognatus . Cognates within the same language are called doublets. Strictly speaking, loanwords from another language are usually not meant by the term, e.g...

 forms in other languages preserve the s: for example, the Sanskrit

Sanskrit

Sanskrit , is a historical Indo-Aryan language and the primary liturgical language of Hinduism, Jainism and Buddhism.Buddhism: besides Pali, see Buddhist Hybrid Sanskrit Today, it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand...

prefix in the name of the language, "put together". Less exact cognates include English same and some, and Latin simul "at the same time" and sīmilis "similar".

Other words in Greek are related, including háma "at the same time", homós "same", and heís "one" (from ).