kotka in English:

1. catkin

English word "kotka"(catkin) occurs in sets:

Fiszki z książki - "Bird Watching" (Edmund Selous)
Fiszki z książki - "Woodland Tales" (Ernest Seton-...
Fiszki z książki - "Getting Acquainted with the Tr...
Fiszki z książki - "Forest Trees of Texas How to K...
Fiszki z książki - "Scientific American Supplement...