Tetrakishexahedron (n.)
definition: A tetrahexahedron.

Tetrakishexahedron is an 18 letter word that begins with a T and ends in an N

Theophilanthropism (n.)
definition: The doctrine of the theophilanthropists; theophilanthropy.

Theophilanthropism is an 18 letter word that begins with a T and ends in an M

Theophilanthropist (n.)
definition: A member of a deistical society established at Paris during the French revolution.

Theophilanthropist is an 18 letter word that begins with a T and ends in a T

Thermoelectrometer (n.)
definition: An instrument for measuring the strength of an electric current in the heat which it produces
Or for determining the heat developed by such a current.
Thermoelectrometer is an 18 letter word that begins with a T and ends in an R

Trachelobranchiate (a.)
definition: Having the gills situated upon the neck; -- said of certain mollusks.

Trachelobranchiate is an 18 letter word that begins with a T and ends in an E

Transmogrification (n.)
definition: The act of transmogrifying
Or the state of being transmogrified; transformation.
Transmogrification is an 18 letter word that begins with a T and ends in an N

Transubstantiation (n.)
definition: A change into another substance.

Transubstantiation is an 18 letter word that begins with a T and ends in an N

Transubstantiation (n.)
definition: The doctrine held by Roman Catholics
That the bread and wine in the Mass is converted into the body and blood of Christ; -- distinguished from consubstantiation and impanation.
Transubstantiation is an 18 letter word that begins with a T and ends in an N

Triplicate-ternate (a.)
definition: Triternate.

Triplicate-ternate is an 18 letter word that begins with a T and ends in an E

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