regular vs systematic

regular is a noun but systematic is not a noun.

Word	Noun	Adjective	Verb	Adverb
regular	Yes	Yes	No	No
systematic	No	Yes	No	No

regular (noun)	systematic (noun)
a garment size for persons of average height and weight
a regular patron
a dependable follower (especially in party politics)
a soldier in the regular army

regular (adjective)	systematic (adjective)
in accordance with fixed order or procedure or principle	characterized by order and planning
(of solids) having clear dimensions that can be measured; volume can be determined with a suitable geometric formula	of or relating to taxonomy
(used of the military) belonging to or engaged in by legitimate army forces
not constipated
relating to a person who does something regularly
officially full-time
not deviating from what is normal
regularly scheduled for fixed times
conforming to a standard or pattern
occurring at fixed intervals
symmetrically arranged
often used as intensifiers
in accord with regular practice or procedure