- lineage
- linear correlation
- linear growth
- linear regression
- linguistic relativity thesis
- linguistics
- Linton, Ralph
- local labour-market
- locality studies
- lock-out
- Locke, John
- Lockwood, David
- logical empiricism
- logical positivism
- logical reduction
- logical universals
- logistic growth
- logistic (or logit) regression
- loglinear analysis
- Lombroso, Cesare
- long-wave theoryz
- longitudinal study
- looking-glass self
- Lorenz curve
- low-trust system
- Lowie, Robert H.
- Luhmann, Niklas
- Lukács, György
- lumpen-bourgeoisie
- lumpenproletariat
