Ordino un caffè doppio.

In Italian, the subject pronoun is often omitted because the verb ending already shows who is doing the action.

• ordino = I order
• The ending -o tells you it is I

So Ordino un caffè doppio is a natural way to say I order a double coffee / a double espresso.
You could say Io ordino..., but that usually adds emphasis, such as I’m the one ordering.

Ordino is the present tense of ordinare (to order).

It can mean:

• I order
• sometimes, depending on context, I am ordering

In a café or restaurant, present tense is commonly used for what you are ordering right now.

The base form, or infinitive, is ordinare, which means to order.

A few present-tense forms are:

• io ordino = I order
• tu ordini = you order
• lui/lei ordina = he/she orders
• noi ordiniamo = we order
• voi ordinate = you all order
• loro ordinano = they order

Un is the masculine singular indefinite article, meaning a or an.

• un caffè = a coffee

Italian usually uses an article here, just as English does in a coffee.
Because caffè is masculine singular, un is the correct form.

The accent mark in caffè shows that the stress falls on the last syllable and that the final vowel is pronounced è.

So it is pronounced roughly caf-FEH, not CAFFe.

This accent is written in standard Italian spelling and should not be omitted in careful writing.

Doppio means double.

In this sentence, un caffè doppio usually means a double espresso or a double coffee, depending on context. In Italy, caffè by itself often means espresso, so caffè doppio is typically understood as a double espresso.

In Italian, adjectives can come after the noun, and this is very common when the adjective is giving a straightforward description.

So:

• caffè doppio = double coffee

This word order is normal and natural in Italian.
English often puts adjectives before the noun, but Italian frequently places them after.

Doppio agrees with caffè, which is a masculine singular noun.

So the adjective must also be masculine singular:

• caffè doppio = masculine singular
• bibita doppia would be feminine singular

Agreement is very important in Italian adjectives.

Yes, it is grammatically correct and understandable, but in real-life situations Italians often use slightly softer or more natural ordering phrases, such as:

• Prendo un caffè doppio. = I’ll have a double espresso.
• Vorrei un caffè doppio. = I’d like a double espresso.
• Un caffè doppio, per favore. = A double espresso, please.

Ordino sounds a bit more like I am ordering or I place an order, so it is correct but a little less common for a casual café request.

In Italy, caffè very often means espresso by default.

So in many real contexts:

• un caffè = an espresso

If you want a different kind of coffee drink, you usually name it specifically, for example:

• un cappuccino
• un caffè americano
• un caffè lungo

That is why un caffè doppio is often understood as a double espresso.

A simple pronunciation guide is:

or-DEE-no oon caf-FEH DOP-pyo

A few notes:

• Ordino: stress on di
• un: pronounced like oon
• caffè: stress on the last syllable, fè
• doppio: the pp is doubled, so it is pronounced with a stronger consonant than a single p

It might be understood, but un caffè doppio is the more natural phrasing for this meaning.

With drinks and menu items, Italian often uses the noun first and then the descriptive adjective:

• caffè doppio
• vino rosso
• pane tostato

So for a learner, un caffè doppio is the safer and more idiomatic choice.