1) Of, pertaining to, or constituting a name or names, a noun or nouns.
From L. nominalis "pertaining to a name or names," from nomen "name," cognate with Pers. nâm, as below.
Nâmenâl, from nâmen, from O.Pers./Av.nâman-, → name, + suffix -al.
nominal focal length
derâzâ-ye kânuni-ye nâmenâl
Fr.: distance focale nominale
An approximate value of the → focal length, used for the classification of lenses, mirrors, or cameras, as opposed to the measured one.
Fr.: valeur nominale
The assigned, specified, or intended value of a quantity.