Proto-Baltic: *sir̃g- (*ser̃g-a-) vb. (1?), *sar̃g-in̂- vb. caus., *ser̃g-ā̂ f.
Meaning: be ill
Lithuanian: sir̃gti (ser̃ga, sir̃gō) `krank sein', sergą̃s 'krank, leidend', caus. sargìnti
Lettish: sìrgt (/sir̃gt PS., C.) (sirgstu/sę̄rgu, sirgu) 'krank sein, kränkeln', sę̄̀rga 'Krankheit, Seuche'