Cecily is a given name, one of the English forms of Latin Cecilia. Notable people with the name include:
Cecily Adams (1958–2004), American actress, casting director, and lyricistCecily Bonville, 7th Baroness Harington (1460–1529), English peeressCecily Brown (born 1969), British painterCecily Lefort (1900–1945), British World War II agentCecily Neville, Duchess of York (1415–1495), mother of two English kingsCecily Norden (1918–2011), South African author and equestrianCecily O'Neill, American theater educatorCecily Polson, Australian actressCecily Strong (born 1984), American actressCecily Tynan (born 1969), Philadelphia broadcast personalityCecily of York (1469–1507), sister of King Edward V of EnglandCecily von Ziegesar (born 1970), American author of novels written for teenagers