fortress

noun

for·​tress ˈfȯr-trəs 

: a fortified place : stronghold

especially : a large and permanent fortification sometimes including a town

fortresslike

ˈfȯr-trəs-līk 

adjective

Synonyms of fortress

• stronghold
• citadel
• fortification
• castle
• bastion
• fort

Examples of fortress in a Sentence

the boys built a snow fortress and then challenged the neighborhood kids to an in-your-face snowball fight

Recent Examples on the Web

Meanwhile, history buffs will love exploring the island’s capital via colorful Spanish-colonial architecture and imposing, ancient fortresses like La Fortaleza and El Morro. —Brittany Chang, Condé Nast Traveler, 30 Jan. 2026

According to local lore, the hillside on which this estate is situated is where a young Napoleon once climbed the cliff below the fortress and carved a heart into the rock. —Abby Montanez, Robb Report, 30 Jan. 2026

Right now, though, Payton is betting he’s built a fortress impenetrable to such thoughts as long as there is still an opponent ahead. —Parker Gabriel, Denver Post, 24 Jan. 2026

This is the task of the middle powers, the countries that have the most to lose from a world of fortresses and most to gain from genuine cooperation. —Haley Ott, CBS News, 21 Jan. 2026

Word History

Etymology

Middle English forteresse, from Anglo-French fortelesce, forteresse, from Medieval Latin fortalitia, from Latin fortis strong

First Known Use

14th century, in the meaning defined above

Kids Definition

fortress

noun

for·​tress ˈfȯr-trəs 

: a fortified place