Plain English Meaning
When you expect to see or hear something, your brain can fill in the gap and make you believe that's what happened — even when it didn't. You hear what you thought was said, not what was actually said.
Full Definition
A cognitive tendency in which a pilot perceives, hears, or interprets information as matching what they expected, rather than what was actually presented. It can cause a pilot to read back a clearance incorrectly, mistake a taxiway for the assigned route, or overlook information that conflicts with their assumption.
Context Anchor
Encountered during taxiing when a pilot follows taxi instructions, checks airport signs and markings, or confirms position on the airport surface.
Derivation
From 'expectation' (Latin exspectare, 'to look for') and '' (a leaning or slant). Together, the term names a leaning of toward what is anticipated.