Administratrix (n.)
definition: A woman who administers; esp.
One who administers the estate of an intestate or to whom letters of administration have been granted; a female administrator.
Administratrix is a 14 letter word that begins with an A and ends in an X

Concavo-convex (a.)
definition: Concave on one side and convex on the other
As an eggshell or a crescent.
Concavo-convex is a 14 letter word that begins with a C and ends in an X

Concavo-convex (a.)
definition: Specifically
Having such a combination of concave and convex sides as makes the focal axis the shortest line between them. See Illust. under Lens.
Concavo-convex is a 14 letter word that begins with a C and ends in an X

Convexo-convex (a.)
definition: Convex on both sides; double convex. See under Convex
A.
Convexo-convex is a 14 letter word that begins with a C and ends in an X

Pneumatothorax (n.)
definition: See Pneumothorax.

Pneumatothorax is a 14 letter word that begins with a P and ends in an X

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