Definition of: exogamy

(eks·og′ə·mē) noun
1. The custom of certain peoples forbidding any man to marry within his own tribe or clan.
2. Marriage outside of one's tribe, clan, or family: opposed to endogamy.
3. Biol. The union of two protozoans of different ancestry, with fusion of nuclei, as the commencement of a new cycle of growth.
—ex·og′a·mous, ex·o·gam·ic (ek′·sō·gam′ik) adjective
EXOGEN
A. Vertical section;
B. Cross-section; showing growth rings for three successive years at 1, 2, 3.
b. Bark.
c. Cambium layer
s. Sapwood (alburnum).
h. Heartwood (duramen).
m. Medullary sheath.
p. Pith.