adjective adi·ac·tin·ic \¦ā-ˌdī-ˌak-¦ti-nik, -ˌdī-ək-\

Definition of adiactinic

  1. :  not transmitting actinic rays

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Origin and Etymology of adiactinic

2a- + diactinic

First Known Use: 1845

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a rounded knoll or a ridge of ice

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