Peerage of England
The ranks of the English peerage are, in descending order, Duke, Marquess, Earl, Viscount, and Baron. While most newer English peerages descend only in the male line, many of the older ones (particularly older baronies) can descend through females. Under English inheritance law all daughters are co-heirs, so many older English peerage titles have fallen into abeyance between various female co-heirs.
Commander (order)
"Knight Commander" or "Dame Commander" is the second most senior grade of seven British orders of chivalry, three of which are dormant (and one of them continues as a German house order). The rank entails admission into knighthood, allowing the recipient to use the title 'Sir' (male) or 'Dame' (female) before his or her name. In the Commonwealth Realms orders and decorations, Knight Commander and Dame Commander rank before Knights Bachelor but after the Order of the Companions of Honour, although Companions of Honour obtain no knighthood or other status.