ONB has 2 meanings
1. What does onb mean?

On, bro

Onb is a messaging abbreviation for "on, bro" that people use to emphasize the truth of a statement or claim (think "on my life, bro"). For example, if your friend doubts your text about seeing Rhianna at a party, you might respond with, "It was her, onb! I'll send you a pic of the back of her head."

It is unclear who came up with the phrase "on, bro" and subsequent abbreviation, but it gained popularity in the late-2010s. As it has gained popularity, people often use onb when texting or messaging online, whether on social media or another platform. They use it similarly to no cap or ISTG.

People might also use onb to agree with something someone else said. In this way, they are confirming the truth of that person's statement, like when someone says, "bet" or "Amen, brotha."


I can't wait for summer.
onb. it's gonna be lit.
Onb tweet

Onb tweet

Related Slang


Updated January 19, 2023
2. What does ONB stand for?

Outward nose breath

When you think something is mildly humorous but not quite funny enough for an LOL response, use "ONB." The acronym stands for "outward nose breath," which is when you laugh through your nostrils but not out loud.

Most people use ONB to react sarcastically to things meant to be funny (but are pretty lame) when texting or messaging online. They may also use it on social media, like Twitter and TikTok.

An example of when you might use ONB is when replying to a lame meme a friend shares online. Or, you might respond to a text from an annoying uncle who shares something he thinks is funny but is actually more offensive.


Check out this vid of me pranking my mom.

President Clinton with the ONB

Related Slang


Updated March 1, 2022

onb definition by Slang.net

This page explains what the acronym "onb" means. The various definitions, examples, and related terms listed above have been written and compiled by the Slang.net team.

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