Definition of "thorough"

I was elected to the Executive Committee of the Vegetarian Society, and made it a point to attend every one of its meetings, but I always felt tongue-tied. Dr. Oldfield once said to me, 'You talk to me quite all right, but why is it that you never open your lips at a committee meeting? You are a drone.' I appreciated the banter. The bees are ever busy, the drone is a thorough idler. And it was not a little curious that whilst others expressed their opinions at these meetings, I sat quite silent. Not that I never felt tempted to speak. But I was at a loss to know how to express myself. All the rest of the members appeared to me to be better informed than I. Then it often happened that just when I had mustered up courage to speak, a fresh subject would be started. This went on for a long time.

1925-29, Mahadev Desai (translator), M.K. Gandhi, The Story of My Experiments with Truth, Part I, chapter xviii

Ye might haue ſeene the frothy billowes fry Vnder the ſhip, as thorough them ſhe went […]

1590, Edmund Spenser, “Book II, Canto XII”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie

You are contented to be led in triumph Thorough the streets of Rome?

1599 (first performance), William Shakespeare, “The Tragedie of Iulius Cæsar”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act V, scene i], line 109

The Ignorance and Idleness of the Plowman, who either goes so shallow, or plows his Thoroughs so wide, or misses Part of the Ground.

1733, William Ellis, Chiltern And Vale Farming Explained