How to Say "main" in Spanish
The most common Spanish word for “main” is “principal” — use this for the most important or central street, road, or element in a location.
principal
preen-see-PAHLpɾinsiˈpal
Examples
La calle principal siempre está llena de gente.
The main street is always full of people.
Mi objetivo principal es terminar mis estudios este año.
My primary goal is to finish my studies this year.
El problema principal con la economía es la falta de empleo.
The chief problem with the economy is the lack of jobs.
Adjective Agreement (Gender)
Even though it describes both masculine and feminine nouns (e.g., 'el edificio principal,' 'la calle principal'), the word 'principal' itself stays the same. It only changes when it becomes plural: 'principales'.
Confusing Adjective and Noun
Mistake: “Usar 'el principal' para decir 'the main' (e.g., 'The main topic is...').”
Correction: Always use it with a noun when it's an adjective: 'El tema principal es...' (The main topic is...).
central
sen-TRAHLθenˈtral
Examples
El parque está en una zona central de la ciudad.
The park is in a central area of the city.
La idea central de su discurso fue la educación.
The main idea of his speech was education.
Necesitamos un punto de encuentro central para todos.
We need a central meeting point for everyone.
Adjective Placement
Like many Spanish adjectives describing inherent quality, 'central' often goes after the noun (e.g., 'el banco central').
Confusing 'Central' and 'Centro'
Mistake: “Using 'el central' when you mean 'the center' (the noun).”
Correction: Use 'central' only to describe something (adjective). The noun for 'the center' is 'el centro'.
primero
pree-MEH-rohpɾiˈme.ɾo
Examples
Es mi primer día en la oficina.
It's my first day at the office.
La primera casa a la derecha es la mía.
The first house on the right is mine.
Llegaron en los primeros lugares de la carrera.
They arrived in the first places of the race.
The Special 'O' Drop Rule
When 'primero' comes right before a masculine word (like 'día' or 'año'), it shortens to 'primer'. Think of it as making room for the word that follows! For example, you say 'el primer día', not 'el primero día'.
Matching the Noun
Like most Spanish adjectives, this word changes to match the thing it describes. Use 'primera' for feminine things ('la primera vez' - the first time) and add an '-s' for plural things ('los primeros pasos' - the first steps).
Forgetting to Shorten It
Mistake: “Fui a España por el primero vez.”
Correction: Fui a España por primera vez. 'Vez' is a feminine word, so you need 'primera'. If it were a masculine word like 'viaje' (trip), you would say 'mi primer viaje' (shortening 'primero' to 'primer').
Using 'Primero' Instead of 'Primer'
Mistake: “Es mi primero coche.”
Correction: Es mi primer coche. Because 'coche' is a masculine word that comes right after it, 'primero' drops the '-o' and becomes 'primer'.
mayor
mah-YORmaˈʝoɾ
Examples
La contaminación es el mayor problema de la ciudad.
Pollution is the city's biggest problem.
La Plaza Mayor es muy bonita.
The main square is very beautiful.
Este proyecto requiere una inversión mayor.
This project requires a greater investment.
'Mayor' vs. 'Más Grande'
Use 'mayor' for abstract things like importance, difficulty, or concern. Use 'más grande' when you're talking about physical size. For example, 'un problema mayor' (a bigger problem) but 'una casa más grande' (a bigger house).
especial
es-peh-see-AHLes.peˈsjal
Examples
Hoy es un día especial para nosotros.
Today is a special day for us.
Ella tiene un talento especial para la música.
She has a special talent for music.
Este plato necesita un ingrediente especial.
This dish needs a special ingredient.
One Form for Masculine & Feminine
Unlike many Spanish adjectives, 'especial' looks the same whether you're describing a masculine or feminine thing. For example: 'un día especial' (a special day) and 'una noche especial' (a special night).
Making it Plural
To talk about more than one special thing, just add '-es' to the end. For example: 'días especiales' (special days) or 'personas especiales' (special people).
Where to Place It
Usually, 'especial' comes after the thing it's describing ('un amigo especial'). But you can put it before to add extra emotion or emphasis, like saying 'an especially special friend' ('un especial amigo').
Trying to make it feminine
Mistake: “La fiesta fue muy especiala.”
Correction: La fiesta fue muy especial. Remember, 'especial' doesn't change for feminine things, so you never need to say 'especiala'.
principales
preen-see-PAH-lehspɾinsiˈpales
Examples
Estas son las razones principales de mi decisión.
These are the main reasons for my decision.
Necesitamos enfocarnos en los problemas principales ahora.
We need to focus on the principal problems now.
Hay tres ingredientes principales en esta receta.
There are three major ingredients in this recipe.
Agreement is Key
Since 'principales' is plural, it must be used with plural nouns, whether they are masculine (los problemas principales) or feminine (las ideas principales).
One Form for Both Genders
Unlike many Spanish adjectives, 'principal' (and 'principales') uses the exact same form whether the noun is masculine or feminine.
Forgetting the Plural
Mistake: “Los problemas principal.”
Correction: Los problemas principales. Remember to match the '-es' ending to the plural noun.
maestro
mah-ESS-trohmaˈes.tɾo
Examples
Necesitamos la llave maestra para abrir todas las puertas.
We need the master key to open all the doors.
El plan maestro detalla cada fase del proyecto.
The master plan details every phase of the project.
Esa es la viga maestra que soporta todo el techo.
That is the main beam that supports the whole roof.
Matching the Noun
When used like this, maestro is an adjective, so it must match the thing it describes. If the noun is feminine, it becomes maestra, like in llave maestra (key) or obra maestra (work of art).
Word Order
This adjective almost always comes right after the noun it's describing, like plan maestro or viga maestra.
arterial
ar-te-ree-ALaɾteˈɾjal
Examples
El doctor dice que mi presión arterial es normal.
The doctor says my blood pressure is normal.
El sistema arterial transporta sangre oxigenada por todo el cuerpo.
The arterial system carries oxygenated blood throughout the body.
Es importante controlar la tensión arterial con regularidad.
It is important to check blood pressure regularly.
One Form for All
This word ends in 'l', which means it stays the same whether the thing you are describing is masculine or feminine. You can say 'el sistema arterial' or 'la presión arterial'.
Placement Rules
In Spanish, adjectives like this usually come AFTER the thing they describe. We say 'blood pressure' (pressure arterial) rather than 'arterial pressure'.
Talking about Roads
Mistake: “Using 'calle arterial' for a main street.”
Correction: In Spanish, we usually call a main street 'una arteria' (a noun) or simply 'una calle principal'. 'Arterial' is almost strictly for medical or biological use.
mero
MEH-rohˈmeɾo
Examples
Lo hice por el mero placer de viajar.
I did it for the mere pleasure of traveling.
Nos vemos en el mero centro de la plaza.
I'll see you right in the center of the square.
Él es el mero jefe de la empresa.
He is the main boss of the company.
Changing for Gender
Since this is an adjective, remember to change the ending to 'mera' if the thing you are describing is feminine, like 'la mera verdad'.
Position Matters
When this word comes before a person or thing, it usually adds emphasis ('the very' or 'the mere') rather than describing a physical quality.
Using 'mero' for 'merely'
Mistake: “Es mero una broma.”
Correction: Es meramente una broma or Solo es una broma.
gordo
GOR-doh (like 'gore' then 'dough')ˈɡoɾðo
Examples
Lo más gordo del problema es la financiación.
The main part/biggest challenge of the problem is the financing.
Ganamos El Gordo de la Lotería de Navidad.
We won the major prize (The Fat One) in the Christmas Lottery.
Neuter Article 'Lo'
When 'lo' is placed before 'gordo,' it creates the phrase 'lo gordo,' which refers to the abstract idea of 'the main part' or 'the essence' of something.
Principal vs. Mayor vs. Central
Learn Spanish with Inklingo
Interactive stories, personalized learning, and more.