yer vs weak yer

yer and weak yer both are nouns.

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

As nouns, weak yer is a hyponym of yer; that is, weak 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.
weak yer: a yer semivowel that was reduced to an ultrashort vowel, and eventually disappeared in a modern Slavic language.

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

yer (noun)	weak 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 reduced to an ultrashort vowel, and eventually disappeared in a modern Slavic language.