What grade level is the word xi?

The word xi is typically considered a 9 level word in the US education system.

How common is the word xi?

In terms of usage frequency, xi is classified as a Rare word.

What is the CEFR level for xi?

xi has a Common European Framework of Reference (CEFR) level of C1.

Is xi a Tier 1, Tier 2, or Tier 3 vocabulary word?

It is classified as a tier 3 word, meaning it is a highly specialized, subject-specific term primarily used in particular domains.

Is xi a Scrabble word?

Yes, xi is a valid Scrabble word. It is valid in both US (NWL) and UK (CSW) dictionaries, worth 9 points.

Is xi valid in Words With Friends?

Yes, it is a valid Words With Friends word worth 9 points.

Is xi a valid Wordle guess?

No, it is not a valid Wordle guess.

Search Dictionary

Definition of xi

xi

/zaɪ/

Plural:xis

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xi Lexical Profile

CEFR

Grade

Tier

Usage

Rare

xi Game Scores & Validity

Scrabble US

Scrabble UK

WWF

Wordle Guess

• noun

The fourteenth letter of the Greek alphabet (uppercase Ξ, lowercase ξ), representing the 'ks' sound.

Example

"In the advanced thermodynamics equation, the lowercase Greek letter xi was used to represent the extent of the chemical reaction."

• Rhymes for xi

• Nearby Words

Word Origin & Etymology

From Greek xi (ξῖ), derived from the Phoenician letter samekh.

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Wordmom. (2026). Definition of Xi. In Wordmom Dictionary. Retrieved Oct 14, 2026, from https://wordmom.com/dictionary/xi