-logy

/-lə.d͡ʒi/

//-lə.d͡ʒi// suffix

"logy" is a 4-letter English headword indexed on PlainSpell.

The verdict

“-logy” is uncommon English (outside the top frequency list), classed as a suffix. The kind of spelling people second-guess.

Unranked
below top-frequency English
5
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A branch of learning; a study of a particular subject.

Corpus desk

Index EN-logy · -logy · English

-logy · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-MID 5 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "-" thin
  • PHOTO-UNK Peer pending

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Key facts for -logy
PropertyValue
Headword-logy
LanguageEnglish
Part of speechSuffix
IPA/-lə.d͡ʒi/
Letters5
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “-logy” in English

-logyfalls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

-logy is uncommon English outside the top frequency list, classed as asuffix, transcribed /-lə.d͡ʒi/. Rarity is why readers land here mid-draft. 2 senses are on record.

-logy doesn't appear in our generated misspelling index, suggesting the orthography follows predictable English patterns. No confusable counterpart is on file for this word, since its spelling is unusual enough that it doesn't cluster with a lookalike.

Etymologically, the entry records: Etymology tree Proto-Indo-European *leǵ- Ancient Greek λόγος (lógos) Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-i-eh₂ Proto-Hellenic *-íā Ancient Greek -ῐ́ᾱ (-ĭ́ā) Ancient Greek -λογῐ́ᾱ (-logĭ́ā)bor. Latin -logialbor. French -l… The correct English form is -logy, spelled --L-O-G-Y.

Definition

  1. 1
    A branch of learning; a study of a particular subject.
  2. 2
    Speech, or a way of speaking, a narrative, logical discourse.

Recorded use

Wiktionary examples

These source excerpts show how -logy appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. Examples: biology, geology, genealogy
  2. Examples: haplology, eulogy, trilogy, apology

Etymology

Etymology tree Proto-Indo-European *leǵ- Ancient Greek λόγος (lógos) Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-i-eh₂ Proto-Hellenic *-íā Ancient Greek -ῐ́ᾱ (-ĭ́ā) Ancient Greek -λογῐ́ᾱ (-logĭ́ā)bor. Latin -logialbor. French -logiebor. English -logy The English -logy suffix originates with loanwords from the Greek, usually via Latin and French, where the suffix -λογία (-logía) is an integral part of the word loaned. E.g. astrology from astrologia, since the 16th century. The French -logie is a continuation of Latin -logia, ultimately from Ancient Greek -λογία (-logía). Within Greek, the suffix is an -ία (-ía) abstract from λόγος (lógos, “account, explanation, narrative”), itself a verbal noun from λέγω (légō, “I say, speak, converse, tell a story”). Within English, the suffix becomes productive, especially to form names of sciences or departments of study, analogous to names of disciplines loaned from the Latin, such as astrology from astrologia or geology from geologia. Original compositions of terms with no precedent in Greek or Latin become common beginning in the later 18th century, sometimes imitating French or German templates (e.g. insectology, attested 1766, after French insectologie; terminology, attested 1801, after German Terminologie). In a third stage, from the 19th century, the suffix becomes productive enough to form nonce combinations with English terms with no Greek or Latin origin, such as undergroundology (1820), hatology (1837). Finally, from the second half of the 19th century, the suffix has also been used as a simplex as ology (plural ologies) and logy (plural logies), in parallel with and often alongside ism (plural isms).

Synonyms

This word in other languages

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "-logy"?
"-logy" is spelled --L-O-G-Y. The IPA pronunciation is /-lə.d͡ʒi/.
What does "-logy" mean?
As a suffix, "-logy" means: A branch of learning; a study of a particular subject.
How do you pronounce "-logy"?
The IPA (International Phonetic Alphabet) transcription for "-logy" is /-lə.d͡ʒi/. 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 "-logy"?
Etymology tree Proto-Indo-European *leǵ- Ancient Greek λόγος (lógos) Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-i-eh₂ Proto-Hellenic *-íā Ancient Greek -ῐ́ᾱ (-ĭ́ā) Ancient Greek -λογῐ́ᾱ (-logĭ́ā)bor. Latin -logialbor.... See the full etymology section above for more details.
Is PlainSpell free to use?
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Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list