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

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

In Japan, where a historic bathing ritual has long been a part of how people unwind there, saunas are being added to onsens. — Winston Ross, Forbes.com, 31 July 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