Definition of "entoderm" [en•to•derm]

• Variant of endoderm. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Beneath the primordial brain an invagination of the ectoderm against the entoderm is formed, later to become the mouth."
• "The inner layer we call the entoderm, the outer the ectoderm; and the "primitive mouth" is known as the blastopore."
• "Finally, the entoderm first forms a broad open gutter, which is shaped like a trough."