The 20 Longest Words In English

If you have hippopotomonstrosesquippedaliophobia (a fear of long words) then this post is not for you! Below you’ll find 20 of the longest words in the English language, starting with the longest one, which is a whopping forty-five letters long!

The Longest Words In English

1. Pneumonoultramicroscopicsilicovolcanoconiosis (45 letters)

A lung disease caused by inhaling very fine silicate or quartz dust, often found in mines.

2. Hepaticocholangiocholecystenterostomies (39 letters)

A surgical creation of a connection between the gall bladder and a hepatic duct and between the intestine and the gall bladder.

3. Hippopotomonstrosesquippedaliophobia (36 letters)

The fear of long words.

4. Supercalifragilisticexpialidocious (34 letters)

A term made popular by the Mary Poppins movie, used to express something that is extraordinary or wonderful.

5. Pseudopseudohypoparathyroidism (30 letters)

A genetic disorder that mimics the symptoms but not the biochemical findings of pseudohypoparathyroidism, leading to short stature, round face, and short hand bones.

6. Floccinaucinihilipilification (29 letters)

The act or habit of describing or regarding something as unimportant or of having no value.

7. Antidisestablishmentarianism (28 letters)

A political position that originated in the 19th century Britain opposing proposals for the disestablishment of the Church of England, meaning it would no longer be the state church.

8. Spectrophotofluorometrically (28 letters)

Relating to or denoting the use of a spectrophotofluorometer, an instrument that measures the amount of light emitted after excitation by a certain spectrum of light.

9. Honorificabilitudinitatibus (27 letters)

The state of being able to achieve honors.

10. Psychoneuroendocrinological (27 letters)

Relating to the study of the interaction between psychological processes and the nervous and endocrine systems of the human body.

11. Electroencephalographically (27 letters)

Relating to the recording or study of brain activity by the electrical potential differences recorded on the scalp.

12. Pneumoencephalographically (27 letters)

Pertaining to or involving pneumoencephalography, a now largely obsolete medical procedure where air or gas is injected into the ventricular system of the brain to help diagnose disorders.

13. Radioimmunoelectrophoresis (26 letters)

A technique combining electrophoresis and radioimmunoassay to provide information about the immune system.

14. Thyroparathyroidectomized (25 letters)

Refers to the surgical removal of the thyroid gland and parathyroid glands.

15. Thyroparathyroidectomize (25 letters)

To perform a surgical removal of the thyroid and parathyroid glands.

16. Microspectrophotometries (24 letters)

Refers to the measurement of the spectra of microscopic samples using spectrophotometry.

17. Dichlorodifluoromethane (23 letters)

A chlorofluorocarbon (CFC) compound having a variety of uses but known for its role in ozone depletion.

18. Incomprehensibilities (21 letters)

The quality of being impossible to understand or comprehend.

19. Disproportionableness (21 letters)

The quality of being out of proportion, not proportionate.

20. Uncharacteristically (20 letters)

Not typical of a particular person or thing.

Read Next