Nazi salute, German, literally "hail victory;" from German Sieg "victory," from Old High German sigu (see Siegfried) + heil "to hail," from Proto-Germanic *hailitho (see health). English heil was used in Middle English as a salutation implying respect or reverence (c. 1200; see hail (interj.)).
salutation in greeting, c. 1200, from Old Norse heill "health, prosperity, good luck," or a similar Scandinavian source, and in part from Old English shortening of wæs hæil "be healthy" (see health; and compare wassail).
The interj. hail is thus an abbreviated sentence expressing a wish, 'be whole,' i. e., be in good health, and equiv. to L. salve, plural salvete, or ave, plural avete .... [Century Dictionary]
<a href="https://www.etymonline.com/word/heil">Etymology of heil by etymonline</a>
Harper, D. (n.d.). Etymology of heil. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/heil