Podlehnik was attested in historical sources as Lihteneck and Leichtenekke in 1259–1260, as Lihtneck in 1297, and as Liehtneck in 1308, among other variants. The Slovene name is a fusedprepositional phrase that has lost case inflection: pod 'under' + Lehnik, referring to the location of the village below Lehnik Castle. The name of the castle is a compound from Middle High Germanlieht 'light, bright' + egge 'hill, peak', thus meaning 'castle on a bright/sunny hill'. The Slovene change of the ending from -negg to -nik is an example of folk etymology based on analogy with many other toponyms ending in -nik.