underflow noun. ['ʌndǝflǝʊ] M19.
[from UNDER- + FLOW noun¹.]
1. An undercurrent (lit. & fig.). M19.

2. The (horizontal) flow of water through the ground, spec. underneath a river-bed. L19.

3. Computing. The generation of a number that is too small to be represented in the device meant to store it. M20.

[TahlilGaran] English Dictionary ▲

underflow verb. [in sense 1 ʌndǝ'flǝʊ; in sense 2 usu. 'ʌndǝflǝʊ] OE.
[from UNDER- + FLOW verb.]
1. verb trans. & intrans. Flow under or beneath (something). rare. OE.

2. verb intrans. Computing. Of the result of an arithmetical operation: become too small for the device meant to store it. M20.

[TahlilGaran] English Dictionary ▲