Noah Webster's New International Dictionary of the English Language

1. (v. t.) To go or move below or under.

2. (v. t.) To be subjected to; to bear up against; to pass through; to endure; to suffer; to sustain; as, to undergo toil and fatigue; to undergo pain, grief, or anxiety; to undergo the operation of amputation; food in the stomach undergoes the process of digestion.

3. (v. t.) To be the bearer of; to possess.

4. (v. t.) To undertake; to engage in; to hazard.

5. (v. t.) To be subject or amenable to; to underlie.