Risk limit
1. The maximum probability, given a tabulation that reports an incorrect outcome, that the audit would not lead to a full manual tabulation that would correct that outcome.
Source: Checking the Paper Record: A Guide for Public Oversight of Tabulation Audits , Verified Voting Foundation, https://www.verifiedvoting.org/wp-content/uploads/2018/09/Checking-The-Paper-Record-Tabulation-Audit-Oversight-Guide.pdf
2. The largest statistical probability that, if an outcome is wrong, the RLA (Risk Limit Audit) does not correct that outcome. For example, assume the reported outcome of an election contest is wrong, and the risk limit for the audit is 5%. In this instance, there is at most a 5% chance that the audit will not correct the wrong outcome, and at least a 95% chance that the audit will correct the wrong outcome. The risk limit is a number between 0 and 1 that limits the risk of certifying an incorrect outcome and is chosen by the RLA administrative authority before the audit is conducted.
Source: 2018 Risk Limiting Audit Pilot Project Report, Orange County Registrar of Voters, https://www.ocvote.com/election-library/docs/2018%20Risk%20Limiting%20Audit%20Pilot%20Project%20Report.pdf