B-Hebrew: The Biblical Hebrew Forum

Judges 1:13 in Accordance BHS Hebrew (ETCBC)
וַֽיִּלְכְּדָהּ֙ עָתְנִיאֵ֣ל בֶּן־קְנַ֔ז אֲחִ֥י כָלֵ֖ב הַקָּטֹ֣ן מִמֶּ֑נּוּ וַיִּתֶּן־ל֛וֹ אֶת־עַכְסָ֥ה בִתּ֖וֹ לְאִשָּֽׁה
When I hover over the yod in אֲחִ֥י I get the following:
ִ֥י i Suffix YodCompagnis
I am going to guess it means something like "Accompanying yod." But I can find no reference to such anywhere.
Any help with what it means?

that yod is attached to 'brother' to turn it into the construct state: 'brother of' (as in 'brother of Caleb').

One has to be very careful not to confuse that yod with the yod for the pronomial suffix: here's how to tell the difference:

אֲחִי 'brother of' (construct state)

אָחִי 'my brother' (pronomial suffix)

Thank you. Is that what the term "yod compagnis" means? I have not found anything about that term anywhere.