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Webster 1913 Edition

Adj.

[See

Of the nature of a quagmire; yielding or trembling under the foot, as soft, wet earth; spongy; boggy.

“O’er the watery strath, or quaggy moss.”

Collins.

Adj.

[supposed to be from the root of quake.]

Yielding to the feet or trembling under the foot, as soft wet earth.