An Etymological Dictionary of the German Language/Annotated/Karg
Karg, adjective, ‘sparing, niggardly,’ from Middle High German karc (g), ‘prudent, cunning, sly, stingy’; in Old High German charag, ‘sad’; a derivative of the Old Teutonic kara, ‘care,’ discussed under Karfreitag. From the primary meaning ‘anxious,’ the three significations ‘sad,’ ‘frugal,’ and ‘cunning’ might be derived; compare Anglo-Saxon čearig, ‘sad,’ and English chary, allied to English care. The syncope of the vowel in Middle High German karc compared with Old High German charag is normal after r.