yer vs strong yer

yer and strong yer both are nouns.

Word	Noun	Adjective	Verb	Adverb
yer	Yes	No	No	No
strong yer	Yes	No	No	No

As nouns, strong yer is a hyponym of yer; that is, strong yer is a word with a more specific, narrower meaning than yer:

yer: Either of two letters in Cyrillic alphabets, which originally represented phonemically the ultra-short vowels in Slavic languages.
strong yer: a yer semivowel that was not reduced to an ultrashort vowel, but instead evolved into different sound in a modern Slavic language.

Other hyponyms of yer include back yer, hard sign, front yer, soft sign, weak yer.

yer (noun)	strong yer (noun)
Either of two letters in Cyrillic alphabets, which originally represented phonemically the ultra-short vowels in Slavic languages.	a yer semivowel that was not reduced to an ultrashort vowel, but instead evolved into different sound in a modern Slavic language.