phenylalanine

/ˌfiːnəlˈæləniːn/

//ˌfiːnəlˈæləniːn// noun

By · According to Wiktionary data (CC BY-SA) ·

"phenylalanine" is a 13-letter English headword indexed on PlainSpell.

The verdict

“phenylalanine” is uncommon English (frequency #67,728 among 46,516 “P” headwords), classed as a noun. The kind of spelling people second-guess.

#67,728
frequency rank, English
46,516
“P” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An essential amino acid C₉H₁₁NO₂ found in most animal proteins; it is essential for growth; the inability to metabolize it leads to phenylketonuria; it is a constituent of aspartame.

Key facts for phenylalanine
PropertyValue
Headwordphenylalanine
LanguageEnglish
Part of speechNoun
IPA/ˌfiːnəlˈæləniːn/
Letters13
Frequency rank#67,728
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “phenylalanine” 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). phenylalanine 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

phenylalanine is uncommon English at frequency #67,728 among 46,516 “P” headwords, classed as anoun, transcribed /ˌfiːnəlˈæləniːn/. Rarity is why readers land here mid-draft. 2 senses are on record.

phenylalanine doesn't appear in our generated misspelling index, which points to an orthography that plays by predictable English rules. Our dataset records no confusable match here, which tends to mean the word is visually distinctive enough to stand on its own.

Etymologically, the entry records: From phenyl + alanine. The correct English form is phenylalanine, spelled P-H-E-N-Y-L-A-L-A-N-I-N-E.

Definition

  1. 1
    An essential amino acid C₉H₁₁NO₂ found in most animal proteins; it is essential for growth; the inability to metabolize it leads to phenylketonuria; it is a constituent of aspartame.
  2. 2
    This molecule or its D-isomer.

Etymology

From phenyl + alanine.

This word in other languages

fenilalanina(Español)phénylalanine(Français)Phenylalanin(Deutsch)

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 "phenylalanine"?
"phenylalanine" is spelled P-H-E-N-Y-L-A-L-A-N-I-N-E. The IPA pronunciation is /ˌfiːnəlˈæləniːn/.
What does "phenylalanine" mean?
As a noun, "phenylalanine" means: An essential amino acid C₉H₁₁NO₂ found in most animal proteins; it is essential for growth; the inability to metabolize it leads to phenylketonuria; it is a constituent of aspartame.
How do you pronounce "phenylalanine"?
The IPA (International Phonetic Alphabet) transcription for "phenylalanine" is /ˌfiːnəlˈæləniːn/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "phenylalanine"?
From phenyl + alanine. 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 “phenylalanine”

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

  • The one correct English spelling is P-H-E-N-Y-L-A-L-A-N-I-N-E - every other letter order is a misspelling in standard orthography.
  • Say it as /ˌfiːnəlˈæləniːn/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • 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