underget
To get less than expected or due.
rare
Some companies hold their clerks responsible to account for the actual amount of the fares on tickets sold, and ignore the question of overgot and undergot money.
Where it comes from
From under- + get. Compare Middle English underyeten (“to comprehend, perceive”), from Old English underġietan (“to understand, perceive, know”).
Adapted from the Wiktionary entry underget (CC BY-SA 4.0).