"Eureka" is an interjection

Interjection

In grammar, an interjection or exclamation is a word used to express an emotion or sentiment on the part of the speaker . Filled pauses such as uh, er, um are also considered interjections...

 used to celebrate a discovery

Discovery (observation)

Discovery is the act of detecting something new, or something "old" that had been unknown. With reference to science and academic disciplines, discovery is the observation of new phenomena, new actions, or new events and providing new reasoning to explain the knowledge gathered through such...

, a transliteration of a word attributed to Archimedes

Archimedes

Archimedes of Syracuse was a Greek mathematician, physicist, engineer, inventor, and astronomer. Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity. Among his advances in physics are the foundations of hydrostatics, statics and an...

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The word comes from 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...

 εὕρηκα heúrēka "I have found (it)", which is the 1st person

Grammatical person

Grammatical person, in linguistics, is deictic reference to a participant in an event; such as the speaker, the addressee, or others. Grammatical person typically defines a language's set of personal pronouns...

 singular

Grammatical number

In linguistics, grammatical number is a grammatical category of nouns, pronouns, and adjective and verb agreement that expresses count distinctions ....

 perfect indicative

Grammatical mood

In linguistics, grammatical mood is a grammatical feature of verbs, used to signal modality. That is, it is the use of verbal inflections that allow speakers to express their attitude toward what they are saying...

 active

Voice (grammar)

In grammar, the voice of a verb describes the relationship between the action that the verb expresses and the participants identified by its arguments . When the subject is the agent or doer of the action, the verb is in the active voice...

 of the verb heuriskō "I find". The reconstructed Ancient Greek pronunciation

Ancient Greek phonology

Ancient Greek phonology is the study of the phonology, or pronunciation, of Ancient Greek. Because of the passage of time, the original pronunciation of Ancient Greek, like that of all ancient languages, can never be known with absolute certainty...

 is hěu̯rɛːka, while the Modern Greek pronunciation

Modern Greek phonology

This page presents a sketch of the phonology of Standard Modern Greek.-Consonants:The consonantal system of Greek is difficult to describe, as there is considerable debate about which sounds to describe as separate phonemes and which to analyse as conditional allophones...

 is ˈevrika.

The accent of the English word is on the second syllable

Syllable

A syllable is a unit of organization for a sequence of speech sounds. For example, the word water is composed of two syllables: wa and ter. A syllable is typically made up of a syllable nucleus with optional initial and final margins .Syllables are often considered the phonological "building...

, following Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 accent rules, which require that a penult (next-to-last syllable) must be accented if it has a long vowel

Vowel length

In linguistics, vowel length is the perceived duration of a vowel sound. Often the chroneme, or the "longness", acts like a consonant, and may etymologically be one, such as in Australian English. While not distinctive in most dialects of English, vowel length is an important phonemic factor in...

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