- by a minimal, insignificant, or almost insufficient amount: This student routinely submits work of substandard or marginally acceptable quality.Pork exports in May were marginally higher compared with the previous year.
- at a barely adequate level: The shelter offers shower and laundry facilities for homeless and marginally housed adults.
- in the margin of a page: It is obvious that Jack London read these books, as they are marked, underlined, and marginally annotated.
- on the border of something: On the wings of butterflies, marginally located contrastive markings create false edges, helping to decrease detection by predators.