SINCE 1828

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actinic focus

noun

Definition of actinic focus

: the focus at which the chemically most effective rays as distinguished from the visually most effective are brought together (as by a lens) — called also chemical focus

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First Known Use of actinic focus

1853

in the meaning defined above

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cathexis

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investment of mental or emotional energy

BROWSE DICTIONARY

Actiniaria

actinic

actinic focus

actinic glass

actinide

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