ACT - Something done, a deed.
AHA - An exclamation of understanding, realization, invention, or recognition.
ATE - Simple past of eat.
CAT - Any similar animal of the family Felidae, which includes lions, tigers, bobcats, etc.
EAT - To consume (something solid or semi-solid, usually food) by putting it into the mouth and swallowing it.
HAT - A covering for the head, often in the approximate form of a cone or a cylinder closed at its top end, and sometimes having a brim and other decoration.
TEA - The dried leaves or buds of the tea plant, Camellia sinensis.
EACH - All; every; qualifying a singular noun, indicating all examples of the thing so named seen as individual or separate items (compare every).
HATE - To dislike intensely; to feel strong hostility towards.
HEAT - Thermal energy.
TECH - Technology.
THAT - The (thing) being indicated (at a distance from the speaker, or previously mentioned, or at another time).
ACHE - To suffer pain; to be the source of, or be in, pain, especially continued dull pain; to be distressed.
ETCH - To cut into a surface with an acid or other corrosive substance in order to make a pattern. Best known as a technique for creating printing plates, but also used for decoration on metal, and, in modern industry, to make circuit boards.
TACT - The sense of touch; feeling.
CHEAT - To violate rules in order to gain advantage from a situation.
TEACH - To show (someone) the way; to guide, conduct.
THETA - The name for the eighth letter οf the Modern Greek alphabet, ninth in Old Greek.
ATTACH - To arrest, seize.
ATTACHE - An official associated with an embassy.