Today's name: Dashiell
Pronunciation: DASH-eel, da-SHEEL, DASH-ull
Potential nicknames: Dash, Dashy, Dashing, Shiell, Shield, Ash, Dal
Origin: Possibly meaning "page boy," or "young man," Dashiell is an Anglicized surname popularized by the author Samuel Dashiell Hammett (whose pen name was Dashiell Hammett), famous for his detective novels. Dashiell, his middle name, was his mother's surname. The name changed over time from the original old French form, de Chiel, to Da Chiell, to Da Shiell, to Dashiell. It can be traced to James de Chiel from Lyon, France, who emigrated to Scotland around 1600. The de Chiells were French Huguenots, and from Scotland they can be traced as finding their way to Maryland, with many ancestors still using Dashiell as a surname.
Fun fact: This name was chosen by Cate Blanchett, C. Thomas Howell, and Helen Fielding for their sons. Alice Cooper may have been the first celebrity to name his son Dashiell, which was in 1985.
Popularity: 120 baby boys were named Dash in 2010 in the U.S., 145 were named Dashiell, and 25 were named Dashiel. In 2011 there were 133 boys named Dash, 124 Dashiell, 37 Dashel and 20 Dashiel. By 2015 the name Dashiell rose to #1102, just outside the top 1000, with 173 births.
Side note: The spelling Dashel seems to be growing more popular. Nicole Sullivan recently used Dashel for her son, and it is a phonetic spelling of Dashiell. If you only prefer one pronunciation it is best to consider how you will spell it. Dashel looks and sounds very similar to the boy's name Cashel.