Old English hæsl, hæsel, from Proto-Germanic *hasalaz (source also of Old Norse hasl, Middle Dutch hasel, German hasel), from PIE *koselo- "hazel" (source also of Latin corulus, Old Irish coll "hazel"). Shakespeare ("Romeo and Juliet," 1592) was first to use it (in print) in the sense of "reddish-brown color of eyes" (in reference to the color of ripe hazel-nuts), when Mercutio accuses Benvolio:
Thou wilt quarrell with a man for cracking Nuts, hauing no reason, but because thou hast hasell eyes.
breakfast dish of oats, fruit, and nuts, eaten with milk or yogurt, 1926, from Swiss-German, from Old High German muos "meal, mush-like food," from Proto-Germanic *mod-sa-, from PIE root *mad- "moist, wet," with derivatives referring to various qualities of food (see mast (n.2)).
"sweetmeat made of almonds and other nuts," 1827, from French nougat (18c.), from Provençal nougat "cake made with almonds," from Old Provençal nogat "nutcake," from noga, nuga "nut," from Vulgar Latin *nucatum (nominative *nuca), from Latin nux (genitive nucis) "nut," from PIE *kneu- "nut" (see nucleus).