Sauces = salads, etymologically speaking
Both salad and sauce originally both meant salted.
The word “salad” came into English during the second half of the 14th century. It travelled through Old Provençal and Middle French from the Vulgar Latin *salata, the feminine singular or neuter plural passive participle of *salare “(to) salt”, meaning “salted [greens]”.
“Sauce” went the same route. But the etymon dates farther back to Classical Latin salsa (preserved in Italian and Spanish), the passive participle of sallere “(to) salt”, also meaning “[something] salted”.
So, next time, when ordering kebab with salad and sauce, try not to think of the fact that you’re requesting salt with salt on your meat.