Old English dæl "dale, valley, gorge," from Proto-Germanic *dalan "valley" (cf. Old Saxon, Dutch, Gothic dal, Old Norse dalr, Old High German tal, German Tal "valley"), from PIE *dhel- "a hollow" (cf. Old Church Slavonic dolu "pit," Russian dol "valley"). Preserved from extinction by Norse influence in north of England.
British physiologist who discovered acetylcholine and, with Otto Loewi, investigated the chemical transmission of nerve impulses. For this work they shared the 1936 Nobel Prize for physiology or medicine.