eructation (n.) Look up eructation at Dictionary.com
"belching," 1530s, from Latin eructationem (nominative eructatio) "a belching forth," noun of action from past participle stem of eructare "to belch forth, vomit," from assimilated form of ex- "out" (see ex-) + ructare "to belch," from PIE *reug- "to belch" (source also of Lithuanian rugiu "to belch," Greek eryge, Armenian orcam), which is probably imitative. Related: Eruct.