Optional [adjective]
Definition of Optional:
possible; available as choice
Sentence/Example of Optional:
The use of a Scripture lesson is, of course, optional with the pastor.
The manner of fastening the ribs to the frame pieces is optional.
Hence we erase all optional marks in the 1st and 3rd rows, but let them stand in the 2nd.
It never occurred to him that that duty was only optional with him now.
It is optional with the judges whether the use of a timepiece is to be allowed.
After they have a school certificate, entrance to the works is optional.
The optional link (JK of fig. 7e) was used in the engines as built.
He was at that moment acutely aware that he did not want to do something which it was optional to do.
The use of books with this class of persons is not optional.
Some are disposed to look upon this matter as optional with them; but such is a mistake.