ppl. a. [UNDER-1 4 a, 10 a.]

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  1.  Supplied with fuel from below.

2

1890.  D. K. Clark, Steam Engine, I. 74. The furnace of an egg-end stationary boiler, under-fired, burning coal.

3

  2.  Insufficiently fired or baked.

4

1891.  Cent. Dict.

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