from The American Heritage® Dictionary of the English Language, 4th Edition
- transitive v. To discharge or excrete from the body.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. To excrete from the body.
from the GNU version of the Collaborative International Dictionary of English
- transitive v. To cast or throw out; to void, as excrement; to excrete, as the indigestible matter of the food; in an extended sense, to excrete by the lungs, skin, or kidneys.
from The Century Dictionary and Cyclopedia
- To discharge or void, as excrement: opposed to ingest.
- To defecate; pass dejecta of any kind.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. eliminate from the body
Latin ēgerere, ēgest-, to carry out : ē-, ex-, ex- + gerere, to carry.(American Heritage® Dictionary of the English Language, Fourth Edition)
From ēgest-, the perfect passive participial stem of the Latin ēgerō ("I carry, bear, or bring out or away”, “I discharge"). (Wiktionary)
The mouth is typically the only opening to the digestive tract, they use the same opening to both ingest food and egest waste.
Another possibility is that zooplankton eat the bacteria, and later egest them unharmed.