arguably

Meanings

1. 1
   adv

   as can be shown by argument

   They are arguably the best.

2. 2
   adv

   As can be supported or proven by sound logical deduction, evidence, and precedent, but without absolute certainty.

   In the early 1770s the bogey figure for opposition politicians was arguably not so much North in the Commons as Mansfield behind the curtain, the country's greatest lawyer (and another Caledonian to gratify the Scotophobes) keeping an irresolute Cabinet committed to waging war in America.

Etymology

From arguable + -ly.