English edit

Etymology edit

From blockhead +‎ -ly.

Adjective edit

blockheadly (comparative more blockheadly, superlative most blockheadly)

  1. (obsolete) Stupid, idiotic.
    • 1792, Thomas Holcroft, Anna St. Ives, vol. V, letter 95:
      Such a blockheadly blunder well deserves castigation!