Adjective

(en adjective)

(Christianity) Bound by religious rule; belonging to a monastic or religious order (often as opposed to (secular)).

* 2002 , , The Great Nation , Penguin 2003, page 201:

A quarter of a million strong in 1680, the clergy was only half as large in 1789. The unpopular regular clergy were the worst affected.

Having a constant pattern; showing evenness of form or appearance.

(geometry, of a polygon) Having all sides of the same length, and all (corresponding) angles of the same size

(geometry, of a polyhedron) Whose faces are all congruent regular polygons, equally inclined to each other.

Demonstrating a consistent set of rules; showing order, evenness of operation or occurrence.

* 2011 , (AL Kennedy), The Guardian , 12 Apr 2011:

April may be the cruellest month, but I am planning to render it civilised and to take my antibiotics in a regular manner.

(now, rare) Well-behaved, orderly; restrained (of a lifestyle etc.).

Happening at constant (especially short) intervals.

(chiefly, US) Having the expected characteristics or appearances; normal, ordinary, standard.

*

, title= Mr. Pratt's Patients, chapter=1 , passage=For a spell we done pretty well. Then there came a reg'lar terror of a sou'wester same as you don't get one summer in a thousand, and blowed the shanty flat and ripped about half of the weir poles out of the sand.}}

(chiefly, military) Permanently organised; being part of a set professional body of troops.

Having bowel movements or menstrual periods at constant intervals in the expected way.

(colloquial) Exemplary; excellent example of; utter, downright.

Belonging to a monastic order or community.

regular clergy, in distinction from the secular clergy

(botany, zoology) Having all the parts of the same kind alike in size and shape.

a regular''' flower; a '''regular sea urchin

(crystallography) isometric

(snowboarding) Riding with the left foot forward. BBC Sport, "Sochi 2014: A jargon-busting guide to the halfpipe", 11 February 2014

(analysis, not comparable, of a Borel measure) Such that every set in its domain is both outer regular and inner regular.

Adjective

(en adjective)

Well grounded or justifiable, pertinent.

*{{quote-magazine, year=2012, month=March-April

, author=(Jan Sapp) , title=Race Finished , volume=100, issue=2, page=164 , magazine=(American Scientist) citation , passage=Few concepts are as emotionally charged as that of race. The word conjures up a mixture of associations—culture, ethnicity, genetics, subjugation, exclusion and persecution. But is the tragic history of efforts to define groups of people by race really a matter of the misuse of science, the abuse of a valid biological concept?}}

I will believe him as soon as he offers a valid answer.

Acceptable, proper or correct.

A valid format for the date is MM/DD/YY.

Do not drive without a valid license.

Related to the current topic, or presented within context, relevant.

(logic) Of a formula or system: such that it evaluates to true regardless of the input values.

(logic) Of an argument: whose conclusion is always true whenever its premises are true.

An argument is valid if and only if the set consisting of both (1) all of its premises and (2) the contradictory of its conclusion is inconsistent.