From Proto-Baltic *rugi-, from Proto-Indo-European *wrugʰyo- (“rye”), itself perhaps a borrowing from a Far Eastern language. Cognates include Lithuanian rugỹs, rugiaĩ, Old Prussian rugis, ruggis, Proto-Slavic *rъžь (Russian, Ukrainian рожь (rož'), Bulgarian ръж (rǎž), Czech rež, Polish reż), Proto-Germanic *rugiz (Old High German rocko, German Roggen, Dutch rogge, Old English ryge, English rye, Old Norse rugr, Swedish råg, Danish rug).
rudzi m (1st declension)
- rye (a grass, Secale sereale, or its grains, used for food or fodder)
sēt, pļaut rudzus ― to sow, to mow rye
lopi sagājuši rudzos ― the animals went into the rye (field)
pūrs rudzu ― portion of rye
malt rudzus ― to pound rye
rudzu maize ― rye bread
There is a singular form rudzis, only sporadically attested (usually to refer to the plant).