first thing

Idioms  

1. Before anything else; without delay. For example, Tom was supposed to call him first thing in the morning. [Late 1500s] Also see under first and foremost; first off.

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Example Sentences

We all doomscroll, which is kind of bad to say, but the first thing I check is my phone.

From Los Angeles Times • Apr. 10, 2026

The first thing patients should check is if their insurance covers GLP-1 drugs for weight loss.

From MarketWatch • Apr. 9, 2026

On affordability, the first thing people here think about is rent.

From Barron's • Apr. 7, 2026

She was joined on the red sofa by her husband Steve, who joked that the "the first thing to go" in their new lives going forward would be the "the alarm clock".

From BBC • Apr. 1, 2026

The first thing I notice is Karly and Sal at the side, arms folded, glaring at me as if I was a piece of dirt they’d just found on their shoes.

From "Code Name Kingfisher" by Liz Kessler