early 14c., "narrative, account," verbal noun from reckon (v.). Meaning "a settling of accounts" is from mid-14c.; that of "calculation" is from late 14c. Compare Dutch rekening "a bill, account, reckoning," Old High German rechenunga, German rechnung, Danish regning "a reckoning, computation." Day of reckoning attested from c. 1600.
reckless
recklessly
recklessness
reckon
reckoner
reckoning
reclaim
reclamation
recline
recliner
recluse