" aperiodicity "

1: as in irregularity, inconsistency;

•  Synonyms : 

•  inconsistence,

•  inconsistency,

•  irregularity,

•  unevenness,

•  capriciousness,

•  changeability,

•  changeableness,

•  fickleness,

•  instability,

•  mutability,

•  unpredictability,

•  unsteadiness,

•  variability,

•  variableness,

•  volatileness,

•  volatility,

•  caducity,

•  evanescence,

•  impermanence

•  Antonyms : 

•  changelessness,

•  constancy,

•  fixedness,

•  immutability,

•  immutableness,

•  invariability,

•  stability,

•  steadiness,

•  unchangeableness,

•  consistency,

•  regularity,

•  sameness,

•  uniformity,

•  durability,

•  enduringness,

•  lastingness,

•  permanence

1: lacking in steadiness or regularity of occurrence;

  * e.g., " ... released aperiodic reports on the results of their cancer research "

•  Synonyms : 

•  casual,

•  catchy,

•  choppy,

•  discontinuous,

•  episodic,

•  erratic,

•  fitful,

•  intermittent,

•  irregular,

•  occasional,

•  spasmodic,

•  spastic,

•  sporadic,

•  spotty,

•  unsteady

•  Antonyms : 

•  constant,

•  continuous,

•  habitual,

•  periodic,

•  regular,

•  repeated,

•  steady