Longest Spanish word

Spanish words can be very long. The average word in the Spanish language contains only 8 characters (7,9 to be exact). However, there are even words that are up to 33 characters long than can be real tongue twisters. Interestingly enough there are a lot of words in the top 100 longest words list that are are enzyms, organic compounds, acids or other terms related to chemistry.

We have created a list of the 100 longest Spanish words. Find the full list underneath. You’ll find the Spanish word, English translation and possibly an explanation of what is (if needed) in all the rows. But first let’s start with the longest word in the dictionary:

The longest word in Spanish:

hipopotomonstrosesquipedaliofobia is the longest Spanish word. This word means the fear or phobia for long words.

100 Longest Spanish words:

See here a list of the 100 longest Spanish words in the dictionary.

Longest Spanish wordsLettersEnglish translationWhat is it?
hipopotomonstrosesquipedaliofobia33hippopotomonstrosesquipedaliophobiaIt is a phobia for / fear for long words. 
supercalifragilisticoexpialidoso32supercalifragilisticexpialidociousMade up word from the movie Mary Poppins (1964)
esternocleidooccipitomastoideo30sternocleidooccipitomastoidA muscle in the neck
amidofosforribosiltransferasa29amidophosphoribosyltransferaseAn enzyme
anticonstitucionalmente23anticonstitutionallyOpposite of constitutional
esternocleidomastoideo22sternocleidomastoidA muscle in the neck
Parangaricutirimícuaro22ParangaricutirimícuaroA village in Mexico
aminometiltransferasa21aminomethyltransferaseAn enzyme
desoxirribonucleótido21deoxyribonucleotideTerm in biochemistry
dinitrofenilhidrazina21dinitrophenylhydrazineAn organic compound
butirilcolinesterasa20butyrylcholinesteraseAn enzyme
carbaminohemoglobina20carbaminohemoglobinA compound
estereoespecificidad20stereospecificityA chemical reaction
esternocleidohioideo20sternohyoidGroup of muscles
institucionalización20institutionalization
otorrinolaringología20otorhinolaryngologyA study of diseases
palmitoiltransferasa20palmitoyltransferaseAn enzyme
acetilcolinesterasa19acetylcholinesteraseAn enzyme
acetilgalactosamina19acetylgalactosamineAn organic compound
administrativamente19administratively
antirrevolucionario19antirevolutionary, counterrevolutionary
betahidroxibutirato19betahydroxybutyrateA chemical
betahidroxibutírico19betahydroxybutyricA organic compound
extraordinariamente19extraordinarily
fluorodesoxiglucosa19fludeoxyglucoseAn organic compound
foliculoestimulante19follicle-stimulatingA hormone
fosfogluconolactona19phosphogluconolactoneAn organic compound
fructooligosacárido19fructooligosaccharideAn organic compound
glicosoaminoglicano19glycosaminoglycanCarbohydrates]
hidroxibenzaldehído19methoxybenzaldehydeAn organic compound
ininterrumpidamente19uninterruptedly
inmunotransferencia19immunoblot, or western blot analysis
otorrinolaringólogo(a)19otorhinolaryngologistSpecialized doctor
postestructuralismo19poststructuralisma philosophy
pseudocolinesterasa19butyrylcholinesteraseAn enzyme
reaprovisionamiento19reprovisionment
seudopeptidoglicano19pseudopeptidoglycanAn organic compound
succiniltransferasa19succinyltransferaseAn enzyme
adrenocorticotropo18adrenocorticotropicA hormone
anticonstitucional18unconstitutional
antropoformización18anthropomorphizationTerm in human psychology.
aristocráticamente18aristocratically
autodescubrimiento18self-discovery
carboxihemoglobina18carboxyhemoglobin
castellanohablante18Spanish speaker (in regions of Spain where other regional languages are prominently spoken)
constitucionalidad18constitutionality
constitucionalismo18constitutionalism
democratacristiano18Christian Democrat
desafortunadamente18unfortunately; regrettably
desvergonzadamente18shamelessly, or unblushingly
electrocardiógrafo18electrocardiograph
electrocardiograma18electrocardiogram
electronegatividad18electronegativity
fosfatidilinositol18phosphatidylinositol
fosfofructoquinasa18phosphofructokinaseAn enzyme
fotodesintegración18photodisintegration
fotosintéticamente18photosynthetically
glucosaminoglucano18glycosaminoglycanA organic compound
gravitacionalmente18gravitationally
imperceptiblemente18imperceptibly
impermeabilización18impermeabilization, waterproof
incondicionalmente18wholeheartedly, unconditionally, unreservedly, unquestioningly
independientemente18independently
internacionalmente18internationally
multidisciplinario18multidisciplinary
nacionalsocialismo18National Socialism; Nazism
nacionalsocialista18National Socialist; Nazi
neoumbilicoplastia18neoumbilicoplastyA procedure
permacongelamiento18permafrost
perpendicularmente18perpendicularly
preternaturalmente18preternaturally
quimioselectividad18chemoselectivity
retrospectivamente18in retrospect
satisfactoriamente18satisfactorily
significativamente18significantly
sobrecalentamiento18overheating
superconductividad18superconductivity
superenrollamiento18supercoilA DNA segment
supervivencialista18A survivalist
termodinámicamente18thermodynamically
tetranortriterpeno18tetranortriterpenoidChemical compounds
accidentariamente17accidentally
acetilglucosamina17acetylglucosamineAn organic compound
acetilneuraminato17acetylneuraminateAn enzyme
acetilneuramínico17acetylneuraminicAn acid
acetiltransferasa17acetyltransferase, transacetylaseAn enzyme
aminociclopropano17aminocyclopropaneAn acid
antiinflacionario17anti-inflationary
aprovisionamiento17provisioning
arrebatadoramente17captivatingly
autodeterminación17self-determination
bacteriorodopsina17bacteriorhodopsina protein
bidimensionalidad17bidimensionality
bosnioherzegovino17someone from Bosnia and Herzegovina
confidencialmente17confidentially
considerablemente17considerably
cuatridimensional17four-dimensional
descentralización17decentralization
desencadenamiento17triggering, unleashing
desnaturalización17denaturation
desventajosamente17disadvantageously, unprofitably, unfavorably
electromagnetismo17electromagnetism
experimentalmente17experimentally
extraoficialmente17unofficially
farmacéuticamente17pharmaceutically
fitohemaglutinina17phytohemagglutinina protein

Let us know if you have seen a word that we missed. We’d be happy to verify and add any words.

Interestingly enough you’ll see that over three quarters of the words are very similar to those in English. We know that English and Spanish vocabulary can be very similar. See our list over “over 750 words that are almost completely the same“. However, this is completely logical since there are so many scientific terms and names on the list which are usually not translated in a much different way throughout different languages.