Plain English Meaning
A solid turning straight into a vapor without melting first, or a vapor turning straight into a solid without becoming liquid in between.
Full Definition
The process by which a substance changes directly from a solid to a gas (or from a gas to a solid) without passing through the liquid phase.
Context Anchor
Seen in aviation weather, icing, and maintenance discussions involving ice, frost, or dry ice.
Derivation
From the Latin sublimare, meaning 'to lift up' or 'raise.' The idea is that the substance is 'lifted' straight from solid form into vapor, skipping the liquid stage entirely.
Why Pilots Care
Sublimation explains how frost can form directly on a cold airframe from in the , and how it can disappear without melting. It matters during in cold , where ice or frost can appear or vanish without any visible .