This is the 7472nd most frequent Polish word.
kos
The Polish word "kos" means "blackbird" (a type of bird).
Here, 'kos' refers to the bird species 'blackbird'.
Kos śpiewa na drzewie.
The blackbird sings on the tree.
In this sentence, 'kosy' is derived from 'kos' to mean 'scythe', which is a farming tool. Here, 'kos' reflects the tool indirectly via its plural form.
Dziadek używał kosy do koszenia trawy.
Grandfather used a scythe to mow the grass.
Here, 'kosy' indirectly discusses the scythe while making a metaphorical connection to the concept of appearance, potentially reflecting the blackbird's relevance.