irregular

Irregular describes something that's unpredictable or uneven. If your dog has irregular spots, it means that she has random splotches of color scattered across her fur.

Anything that doesn't have a pattern or schedule is irregular, like the irregular hours of a store that's only open when the owner feels like it. In grammar, an irregular part of speech is one that doesn't stick to the usual rules. Irregular can also describe something doesn't meet standards, like irregular clothing that's sold at a discount. Irregular originally meant "not in conformity with Church rules."

Primary Meanings of irregular

1.
adjn
(of a surface or shape); not level or flat or symmetrical
merchandise that has imperfections; usually sold at a reduced price without the brand name
2.
adj
deviating from normal expectations; somewhat odd, strange, or abnormal
3.
nadj
a member of an irregular armed force that fights a stronger force by sabotage and harassment
(used of the military) not belonging to or engaged in by regular army forces
Full Definitions of irregular
1

adj (of a surface or shape); not level or flat or symmetrical

“walking was difficult on the irregular cobblestoned surface”
Synonyms:
uneven
not even or uniform as e.g. in shape or texture

adj (of solids) not having clear dimensions that can be measured; volume must be determined with the principle of liquid displacement

Antonyms:
regular
(of solids) having clear dimensions that can be measured; volume can be determined with a suitable geometric formula

adj falling below the manufacturer's standard

irregular jeans”
Synonyms:
imperfect
not perfect; defective or inadequate

n merchandise that has imperfections; usually sold at a reduced price without the brand name

Synonyms:
second
Type of:
merchandise, product, ware
commodities offered for sale
2

adj deviating from normal expectations; somewhat odd, strange, or abnormal

“highly irregular behavior”
Synonyms:
atypical
abnormal, unnatural
not normal; not typical or usual or regular or conforming to a norm

adj contrary to rule or accepted order or general practice

irregular hiring practices”
Synonyms:
illegal
prohibited by law or by official or accepted rules
asymmetrical, crooked
irregular in shape or outline
casual, occasional
occurring from time to time
improper, unconventional, unlawful
not conforming to legality, moral law, or social convention
randomised, randomized
set up or distributed in a deliberately random way
strong
of verbs not having standard (or regular) inflection
unrhythmic, unrhythmical
not rhythmic; irregular in beat or accent
rough, unsmooth
having or caused by an irregular surface
unsteady
subject to change or variation
asymmetric, asymmetrical
characterized by asymmetry in the spatial arrangement or placement of parts or components
unsystematic
lacking systematic arrangement or method or organization
Antonyms:
regular
in accordance with fixed order or procedure or principle
first-string
of members of a team; not substitutes
lawful, rule-governed
according to custom or rule or natural law
official, prescribed
conforming to set usage, procedure, or discipline
standard, stock
regularly and widely used or sold
timed
regularly spaced in time
uniform
evenly spaced
weak
(used of verbs) having standard (or regular) inflection
well-ordered
ordered well
rhythmic, rhythmical
recurring with measured regularity
symmetric, symmetrical
having similarity in size, shape, and relative position of corresponding parts
systematic
characterized by order and planning
show more antonyms...

adj lacking continuity or regularity

“an irregular worker”
Synonyms:
temporary
part-time, parttime
involving less than the standard or customary time for an activity

adj not occurring at expected times

Synonyms:
unpredictable
sporadic
recurring in scattered and irregular or unpredictable instances

adj independent in behavior or thought

“she led a somewhat irregular private life”
Synonyms:
maverick, unorthodox
unconventional
not conforming to accepted rules or standards
3

n a member of an irregular armed force that fights a stronger force by sabotage and harassment

Synonyms:
guerilla, guerrilla, insurgent
Types:
Maquis, Maquisard
a guerrilla fighter in the French underground in World War II
urban guerrilla
a guerrilla who fights only in cities and towns
Type of:
warrior
someone engaged in or experienced in warfare

adj (used of the military) not belonging to or engaged in by regular army forces

irregular troops”
irregular warfare”
Synonyms:
partisan, partizan
devoted to a cause or party
Antonyms:
regular
(used of the military) belonging to or engaged in by legitimate army forces
standing
permanent
show more antonyms...

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.