Such [books] as are mere pieces of formality, so that if you look
on them, you look though them.
Fuller.
3. Compliance with formal or conventional rules; ceremony;
conventionality.
Nor was his attendance on divine offices a matter of formality and
custom, but of conscience.
Atterbury.
4. An established order; conventional rule of procedure; usual method;
habitual mode.
He was installed with all the usual formalities.