a.
1.
Express, explicit, positive, strict, official, in due form, according to established form.
2.
Regular, methodical, set, fixed, rigid, stiff.
3.
Ceremonious, precise, punctilious, stiff, starch, starched, prim, affectedly exact.
4.
Constitutive, essential.
5.
External, as mere form, merely ~.
6.
( Met. ) Organic, formative, primordial, innate, a priori .