What does API stand for?

API stands for Application Programming Interface. It is a standardized set of rules that describes how software applications can communicate with each other and share data.

How do you use API in a sentence at work?

You typically use API as a noun. Examples: We called the Google Maps API to display locations. / The API requires authentication with an API key. / Our backend exposes a REST API for mobile clients.

Is API formal or informal?

API is neutral in formality. It is used equally in formal technical documentation, casual team conversations, and interviews. It is professional and standard across all contexts in tech.

What is the difference between an API and a library?

A library is code you import directly into your application, while an API is a set of rules for communication between separate applications, often accessed over the network.

Do I need to know how an API works internally?

No. As a developer using an API, you only need to know how to call it and what data it returns. You do not need to understand its internal implementation unless you are building the API.

API meaning in tech — Speak Tech English

Commonness	5/5
Versatility	5/5
Formality	CasualFormalNeutral
Spoken ↔ Written	SpokenWrittenBoth
Directness ↔ Diplomatic	DirectDiplomaticDirect
Region	US and UK

Say it like this

✓We need to expose an API for third-party developers

✓Call the API to fetch user data

✓The API documentation is unclear

Real examples

in a standup

"Yesterday I finished integrating the payment API so customers can now check out directly from our app."

in a code review

"Make sure this endpoint follows our API design standards before we merge."

in a team meeting

"The third-party API we relied on went down, which is why our service was unavailable for two hours."

Don't say this

Handle with care. Non-native speakers sometimes treat API as a verb (APIing) when it should remain a noun. API is not a tool you use, but a set of rules and protocols that enables communication between systems.

✕We are APIing the database connection.

✓We are using an API to connect to the database.— API is a noun, not a verb. You do not API something; you use or call an API.

✕This API tool helps us integrate payments.

✓This payment API allows us to integrate payments into our app.— An API is not a tool itself; it is a set of protocols and rules that enables communication between applications.

✕The API is very slow because it downloads too much data.

✓The API response is slow because the server is overloaded.— The API itself is not slow; rather, the server providing the API or the network connection may be slow.

Other forms

noun

API

"The REST API returns JSON formatted data."

noun

APIs

"We use several third-party APIs to enhance our platform."

adjective

API (used as modifier)

"Our API documentation is available on GitHub."

Often used with

call an APIto make a request to an API endpoint

REST APIAPI using REST architectural principles, very common in web development

API endpointa specific URL where an API can be accessed

API keya unique identifier used to authenticate API requests

API documentationwritten instructions explaining how to use an API

third-party APIan API provided by an external company or service

Similar words

interfaceGeneric term, but API is more specific to software communication

protocolSet of rules, but protocol is broader; API is a specific type of protocol

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Practice

Try it

4 quick exercises

Pick the most natural phrasing

1. Your teammate asks how to get weather data from an external service. What do you say?

We need to call their weather API to get the data.We need to API their weather service.We need to use their weather APIing system.We need to API the weather data.

Complete the sentence

2. We cannot deploy until the _______ is fully documented and tested.

Spot the mistake

3. Which sentence uses API incorrectly?

Our mobile app communicates through a REST API.The API provides access to user information.We are APIing the new payment system.This API endpoint returns customer data.

Rewrite naturally

4. Rewrite in natural tech English: 'We made a request to the service and received a response with the information we needed.'

Questions

Quick poll

Have you said "api" in a standup this week?

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