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see also ento-.

A common prefix, as in the following terms:

in comb. =Greek endon within, as: -car- dium, lining membrane of heart; -carp, inner layer of pericarp; -crane, inner surface of skull; -derm, inner layer of blastoderm; -gamous, -gamy, (of) marrying within the tribe; -gen, plant that develops wood in interior of stem; -genous, growing from within; -lymph, fluid in membranous labyrinth of ear; -metritis, -metrium, (inflammation of) lining membrane of womb; -morph, mineral enclosed in another; -parasite, internal parasite; -plasm, -sarc, inner soft layer of protoplasm; -scope, instrument for viewing internal parts of body; -skeleton, internal framework of vertebrates; endo\'smose, -osmo\'sis, passage of a fluid inwards through a porous septum; -sperm, albumen enclosed with embryo in seeds; -spore, inner coat of spore, spore formed in a case; -the lium, layer of cells lining blood-vessels &c.