dial. and techn. [f. KNOB sb.]

1

  a.  To knock, etc.; spec. = KNAP v.1 2, KNOB v. 3. b. Metallurgy. To shingle; also NOBBLE, q.v.

2

1842–76.  Gwilt, Archit. (ed. 7), Gloss., Knobbling, knocking off the rough protuberances of hard rock stone at the quarry.

3

1863–9.  Dict. Archit., Knobbling, the term used near London and in the west of England for … reducing a mass of stone in the quarry to a somewhat square block…. In flint work it is called ‘knapping.’

4

1876.  Whitby Gloss., Knobble, v. to strike with a club.

5

1879.  Miss Jackson, Shropsh. Word-bk., Knobble, to hammer; to knock, but not forcibly.

6

1881.  Raymond, Mining Gloss., Knobbling-fire, a bloomary for refining cast-iron.

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