underreact

American  

[uhn-der-ree-akt] / ˌʌn dər riˈækt /

verb (used without object)

1. to react with less than the expected or appropriate emotion.

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Other Word Forms

• underreaction noun

Etymology

Origin of underreact

First recorded in 1965–70; under- + react

Example Sentences

These earnings beats appear to be more of a surprise, and because investors tend to cling to their prior beliefs, they underreact to the unexpectedly good news.

From Barron's • Mar. 24, 2026

Doves think the current situation bears little resemblance to 2021-22 and fret that the Fed will underreact to labor-market slowing.

From The Wall Street Journal • Nov. 12, 2025

For immunocompromised patients, Kmush said, the concern is generally that their systems would underreact — not overreact — to the shots.

From Washington Post • Nov. 28, 2021

This was an example, he said, of experts hedging language to make sure the public didn’t over- or underreact.

From New York Times • Jul. 22, 2020

In short, the lack of contact tracing guarantees that Americans — collectively and individually — will both overreact and underreact to the virus, because we don't have the information we need to react appropriately.

From Salon • Jun. 23, 2020