undergo Look up undergo at Dictionary.com
O.E. undergan "undermine," from under + gan (see go). Cf. M.Du. ondergaen, O.H.G. untarkun, Ger. untergehen, Dan. undergaa. Sense of "submit to, endure" is attested from c.1300. Meaning "to pass through" (an alteration, etc.) is attested from 1634.