onsen

noun

on·​sen ˈȯn-ˌsen 

ˈän-

plural onsens or onsen

1

a

: a Japanese hot spring

When Japan began to modernize in the late 1800s, trains made it relatively easy for city dwellers to travel to the countryside, and traditional-style inns … sprang up around the onsen …

—Andrew Curry

b

: a traditionally Japanese resort or hotel with hot springs

2

: a Japanese bath in which bathers soak in a hot spring or hot-spring fed bath after first cleansing with a shower

The Japanese tradition of onsen (public baths) is high on the list of après-ski activities in Niseko [Japan].

—Jenny Hewett

also : a bathhouse or room used for such a bath

Examples of onsen in a Sentence

Recent Examples on the Web

Priority Pass now encompasses more than 1,900 lounges and experiences globally, ranging from traditional lounges to sleep pods, spas, gaming spaces and even an onsen overlooking an airport runway in Japan. — Jeff Fromm, Forbes.com, 18 Aug. 2026

After eating, take a walk around the nearby bamboo forest path, then return for time in the onsen. — Catherine Garcia, TheWeek, 3 Aug. 2026

To experience Japan’s famous onsen culture with fewer crowds, head to the rural hot spring town of Nagato Yumoto. — Jessica Kozuka, Travel + Leisure, 2 Aug. 2026

Sleek rooms were designed by Andre Fu, there’s a central courtyard garden that pivots around a huge cherry tree, and expansive hot spring onsen pools in the basement. — Condé Nast, Condé Nast Traveler, 2 June 2026

Word History

Etymology

borrowed from Japanese, from on "warm" + sen "spring, fountain"

First Known Use

1896, in the meaning defined at sense 1