chaff 1 (chăf)
1. Botany Thin dry bracts or scales, especially:
a. The dry bracts enclosing mature grains of wheat and some other cereal grasses, removed during threshing.
b. The scales or bracts borne on the receptacle among the small individual flowers of many plants in the composite family.
2. Finely cut straw or hay used as fodder.
3. Trivial or worthless matter: ignored the picky, unimportant criticisms that were just a lot of chaff.
4. Strips of metal, foil, or glass fiber with a metal content, cut into various lengths and having varying frequency responses, that are used to reflect electromagnetic energy as a radar countermeasure. These materials, usually dropped from aircraft, also can be deployed from shells or rockets.
[Middle English chaf, from Old English ceaf.]
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