ostrów

Etymology
.

Noun

 * 1) type of river island, with ground relatively high above the water level and usually covered with forest

Usage notes
This gender form is used in modern speech and most places names, e.g. . The feminine noun with the same nominative singular form found in the city name is etymologically unrelated.

Declension

 * The genitive singular is usually ostrowu but more rarely ostrowa.