certain
sure; not in doubt
Root
- cert: sure, settled, made certain
Other words with the cert root
- ascertain: to find out or make certain
- certainty: sureness
- certificate: document that certifies something
- certification: official confirmation or credential
- certified: officially confirmed or qualified
- certify: to confirm officially as true
- certitude: complete certainty
Certain means settled enough that doubt quiets down.
After checking the source table, she was certain the summary had dropped a row.