This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. Simple past tense and past participle of reckon.

"Notice that time in this calendar is not reckoned from the creation of the world AKA Ussher but from the creation of Adam."

to reckon upon   

reckoned    reckoning    reckons   

rely    trust    swear    bank    judge    guess    gauge    approximate    estimate   

to reckon without one's host    to reckon for    guess    calculate   

reckon without    reckon for    reckon on    reckon upon    reckon with   

count    enumerate    number    calculate    account    esteem    repute    suppose    settle    compute   

beckon    second   

retribution    computation    latitude    longitude