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FoC
focaccia
focal
focal distance
focal infection
focal length
focal-plane shutter
focal point
focal ratio
focalize
foci
focus
focus group
focused
focussed
fodder
FOE
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focal ratio
fo·cal ra·tio


noun 
Definition:
 
optics 
Same as  f-number
Encarta® World English Dictionary [North American Edition] © & (P)2009 Microsoft Corporation. All rights reserved. Developed for Microsoft by Bloomsbury Publishing Plc.
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