Funny that lots of words can be guessed correctly if one knows a few European languages. I speak Dutch, German, Russian, English and was able to recognize most of the words without ever using it in English. For example Seldom. It's very similar to Zelden in Dutch. I would never use the word Seldom though.
Seldom is one of those words that's used occasionally in writing, but seldom in conversation.
Funny enough I started using the word seldom more often in English, my native language, after I learned Swedish to fluency. Swedish has the word sällan which is cognate with the English word seldom but it’s commonly used in both spoken and written Swedish. Languages are fun!