altgrade

alta (“high”) +‎ grado (“degree”) +‎ -e (“adverbial suffix”).

altgrade

1. to a high degree, highly
   • L. L. Zamenhof (translator), “Fluganta kofro” (“The Flying Trunk”) in Fabeloj Book 1, by Hans Christian Andersen,

     “Mi trovas tion plej altgrade nekonvena,” esprimis sian opinion la tekaldrono, kiu plenumadis la oficon de kuireja kantisto kaj estis duonfrato de la samovaro, “ke oni aǔskultu fremdan birdon. [...]”

     ‘I think it highly improper (lit. improper to the highest degree),’ said the tea-kettle, who was kitchen singer, and half-brother to the tea-urn, ‘that a rich foreign bird should be listened to here. [...]’

   • Willy van Zoest (translator), Blua Sango by Billy Wood, Chapter 2,

     Sed la maljuna grafo estis altgrade, necedeble fiera [...]

     But the old count was highly, unyieldingly proud [...]