'FOCAL' definitions:

Definition of 'focal'

(from WordNet)
adjective
Having or localized centrally at a focus; "focal point"; "focal infection"
adjective
Of or relating to a focus; "focal length"

Definition of 'Focal'

From: GCIDE
  • Focal \Fo"cal\, a. [Cf. F. focal. See Focus.] Belonging to,or concerning, a focus; as, a focal point. [1913 Webster]
  • Focal distance, or length, of a lens or mirror (Opt.), the distance of the focus from the surface of the lens or mirror, or more exactly, in the case of a lens, from its optical center.
  • Focal distance of a telescope, the distance of the image of an object from the object glass. [1913 Webster]

Acronyms for 'focal'

From: V.E.R.A.
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