element of the name is the name of a people, the Ligore (whose name appears in Ligera ceastre in the genitive plural form); their name came in turn from the river Ligor (now the River Soar), the origin of whose name is uncertain but thought to be from Brittonic (possibly cognate with the name of the Loire).

The second element of the name is the Old English word ceaster ("(Roman) fort, fortification,