dead drift
A presentation in which the fly moves at exactly the same speed as the current, with no drag or unnatural movement — as if it were a real insect, helpless, carried by the water. Achieving a perfect dead drift requires constant adjustment of the line to prevent the current from pulling the fly faster or slower than the water around it. It is the foundational discipline of fly fishing.
Etymology
Angling terminology — the fly is "dead" in the sense of passive, drifting without agency.
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