17th In Spanish | Exact Word And Usage

In Spanish, 17th is decimoséptimo for masculine nouns and decimoséptima for feminine nouns.

If you want to say 17th in Spanish, the standard ordinal form is decimoséptimo. That form changes with gender, so you’ll also see decimoséptima. In plain English, that means Spanish treats “17th” like an adjective that agrees with the noun it describes.

This is where many learners get tripped up. They know diecisiete means “seventeen,” then they try to stretch it into an ordinal. That doesn’t work. Spanish uses a different word family for ordinal numbers, and 17th belongs to that pattern.

If you just need the answer, here it is:

• 17th masculine singular:decimoséptimo
• 17th feminine singular:decimoséptima
• 17th masculine plural:decimoséptimos
• 17th feminine plural:decimoséptimas

What 17th Means In Spanish

An ordinal number shows position in a sequence. So “seventeen” counts how many, while “17th” shows place or order. In Spanish, that switch matters. You move from the cardinal number diecisiete to the ordinal decimoséptimo.

You’ll use it with nouns such as floor, chapter, century, anniversary, or edition. A few common patterns look like this:

• el decimoséptimo día — the 17th day
• la decimoséptima página — the 17th page
• el decimoséptimo capítulo — the 17th chapter
• la decimoséptima edición — the 17th edition

Spanish grammar authorities treat these forms as true ordinals. The RAE’s entry on ordinal numbers lays out how ordinal numerals work, while the RAE’s spelling rules for ordinal numerals explain their written forms.

17th In Spanish In Everyday Use

In daily speech, native speakers often avoid higher ordinals and use the cardinal number instead, based on the setting. You’ll hear this a lot with kings, popes, street names, dates, and item numbers. Still, for standard learning, tests, writing, and careful usage, decimoséptimo is the form you should know first.

That’s why textbooks teach the ordinal. It gives you the clean, full form. Once you know it, you can spot where native use gets looser and where formal Spanish sticks to the full ordinal.

Masculine And Feminine Forms

The ending changes to match the noun. If the noun is masculine, use decimoséptimo. If it is feminine, use decimoséptima. That agreement rule also applies in plural.

Try these side by side:

• el decimoséptimo piso — the 17th floor
• la decimoséptima planta — the 17th floor
• los decimoséptimos juegos — the 17th games
• las decimoséptimas jornadas — the 17th sessions

One-Word And Two-Word Spellings

You may also run into décimo séptimo and décima séptima. Those forms are accepted. Still, current academic usage prefers the one-word form for numbers in this range, so decimoséptimo and decimoséptima are the safer picks in polished writing. Fundéu explains that preference in its note on writing ordinal numbers.

The accent mark matters too. In the one-word form, it goes on the sép part: decimoséptimo. Misspelling that accent is a common slip.

Use Case	Spanish Form	Meaning
Masculine singular	decimoséptimo	17th with a masculine noun
Feminine singular	decimoséptima	17th with a feminine noun
Masculine plural	decimoséptimos	17th with masculine plural nouns
Feminine plural	decimoséptimas	17th with feminine plural nouns
Accepted split spelling	décimo séptimo	Two-word masculine form
Accepted split spelling	décima séptima	Two-word feminine form
Cardinal number	diecisiete	Seventeen, not 17th
Numeric abbreviation	17.º / 17.ª	Short ordinal form in writing

How To Use 17th Naturally In A Sentence

Memorizing the word is only half the job. You also need to place it smoothly. In Spanish, ordinals often come before the noun, though they can appear after it in some set expressions or formal styles.

Here are solid model sentences:

• Hoy es el decimoséptimo día del mes. — Today is the 17th day of the month.
• Ella vive en la decimoséptima casa de la calle. — She lives in the 17th house on the street.
• Leí el decimoséptimo capítulo anoche. — I read the 17th chapter last night.
• Es la decimoséptima vez que veo esa película. — It’s the 17th time I’ve seen that movie.

Those examples show the pattern clearly: article + ordinal + noun. Once that clicks, the word stops feeling stiff and starts feeling usable.

Dates Versus Order

This is a spot where English habits can throw you off. In English, “the 17th” often refers to a calendar date. In Spanish, dates are usually read with cardinal numbers, not ordinals, apart from primero for the first day of the month in many contexts.

So if you mean a date, Spanish usually says el diecisiete de mayo, not el decimoséptimo de mayo. If you mean order or rank, then the ordinal form fits.

Common Mistakes With 17th In Spanish

Most mistakes fall into a handful of patterns. Catch these early and your Spanish will look cleaner right away.

Mixing Up Cardinal And Ordinal Numbers

Diecisiete means “seventeen.” It does not mean “17th.” If the sentence is about order, rank, or position, you need the ordinal.

Forgetting Gender Agreement

Decimoséptimo piso is correct. So is decimoséptima página. Swapping those endings sounds off.

Dropping The Accent Mark

Decimoseptimo without the accent is a spelling error. The standard one-word form is decimoséptimo.

Using The Ordinal For Dates

When you mean a day of the month, Spanish usually goes with the cardinal number: el diecisiete. Save decimoséptimo for position in a sequence.

Wrong Form	Better Form	Why
diecisiete piso	decimoséptimo piso	Cardinal replaced with ordinal
decimoséptimo página	decimoséptima página	Gender must match the noun
decimoseptimo	decimoséptimo	The accent mark is required
el decimoséptimo de abril	el diecisiete de abril	Dates usually take cardinals

Memory Tricks That Stick

A neat way to lock this in is to connect 17th with 10th plus 7th. Spanish builds that idea into the word: décimo plus a form linked to séptimo. That’s why the middle of the word sounds familiar once you’ve learned lower ordinals.

You can also practice in short clusters:

• quinto — 5th
• séptimo — 7th
• décimo — 10th
• decimoséptimo — 17th

That pattern helps your ear. Instead of treating the word like a random chunk, you start hearing its parts.

When You’ll Actually Need This Word

You may not say “17th” every day, yet it shows up in more places than people expect. Schoolwork, books, rankings, hotel floors, sports editions, chapter titles, anniversaries, and formal descriptions all use ordinals. If you read Spanish often, you’ll run into this form sooner than you think.

It also helps with recognition. Even if native speakers switch to a cardinal in casual speech, seeing decimoséptimo in print won’t slow you down once you know what it means.

So the clean answer is simple: decimoséptimo or decimoséptima, based on the noun. Learn the word, match the gender, keep the accent, and use cardinals for most calendar dates. That’s the full picture without the fluff.