Definition
The upward angle of an airplane's wings when viewed from the front, where the wingtips sit higher than the wing roots. Dihedral contributes to lateral stability by causing the airplane to roll back toward level flight after a disturbance such as a gust.
Plain English
The wings are angled slightly upward, like a shallow V. This shape helps the airplane right itself if a gust tips it sideways.
Context Anchor
Seen in discussions of airplane stability, handling, and how the airplane responds after it is disturbed from level flight.
Derivation
From Greek 'di-' (two) and 'hedra' (seat or surface), meaning two surfaces meeting at an angle. In aviation, the two surfaces are the left and right wings meeting at the fuselage with an upward slope.
Why Pilots Care
The dihedral angle supplies inherent lateral stability, helping the airplane return to wings-level flight after a disturbance with little pilot input.
Analogy
From the front, wings with dihedral look a little like a shallow letter V. That shape helps the airplane naturally settle back toward level, much like a weighted toy tends to right itself after being tipped.
Intuition Check
Dihedral does not mean the wings sweep backward or forward. It means the wings angle upward from the airplane’s centerline toward the tips.
Example Sentence 1
The Cessna 172's noticeable dihedral helps the airplane roll back to level after a wing is lifted by a gust.
Example Sentence 2
A pilot noticing excessive roll response may check whether the airplane’s dihedral was altered during maintenance.