Definition of "at best"

at best

prepositional phrase
1. In the most favorable of conditions; at the most.
  Quotations
  Steve Bruce's side have swung from highs to lows in what has been at best a wildly inconsistent start to the season. They experienced a microcosm of this within the opening 45 minutes at the Stadium of Light.
  2011 October 1, Phil Dawkes, “Sunderland 2 - 2 West Brom”, in BBC Sport‎
  The power of federal officials to issue a national vaccine mandate is questionable at best.
  2021 August 6, “Get Vaccinated. Get Masked. It’s the Only Way Out of This.”, in The New York Times‎
  It recalls the business case for Scotland's reopening of the Borders Railway to Tweedbank, that British Rail closed in 1969. The review says the business case for this was at best borderline, but goes on to say that the case greatly underestimated passenger demand and that the railway Scotland built has capped its capacity.
  2023 September 6, Philip Haigh, “£30 billion plan to transform the rail network in Ireland”, in RAIL, number 991, page 25