XSS

noun

"xss" is a 3-letter English headword indexed on PlainSpell.

The verdict

“XSS” is uncommon English (frequency #92,265 among 1,183 “X” headwords), classed as a noun. The kind of spelling people second-guess.

#92,265
frequency rank, English
1,183
“X” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Abbreviation of cross-site scripting.

Key facts for XSS
PropertyValue
HeadwordXSS
LanguageEnglish
Part of speechNoun
Letters3
Frequency rank#92,265
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “XSS” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). XSS lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Rare enough to double-check

XSS is uncommon English at frequency #92,265 among 1,183 “X” headwords, classed as anoun. Rarity is why readers land here mid-draft. Gloss: "Abbreviation of cross-site scripting.".

XSS doesn't appear in our generated misspelling index, a sign its spelling follows regular English conventions. This entry stands alone in our confusable dataset, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.

Etymologically, the entry records: The X denotes cross. CSS was avoided because of the potential for confusion with the existing Web technology named cascading style sheets. The correct English form is XSS, spelled X-S-S.

Definition

  1. 1
    Abbreviation of cross-site scripting.

Etymology

The X denotes cross. CSS was avoided because of the potential for confusion with the existing Web technology named cascading style sheets.

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "XSS"?
"XSS" is spelled X-S-S.
What does "XSS" mean?
As a noun, "XSS" means: Abbreviation of cross-site scripting.
What is the origin of the word "XSS"?
The X denotes cross. CSS was avoided because of the potential for confusion with the existing Web technology named cascading style sheets. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “XSS”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is X-S-S - every other letter order is a misspelling in standard orthography.
  • Browse more English words and confusable pairs in the same reference. English words

Other uncommon English words near this rank

Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list