ACT - Something done, a deed.
ANT - Any of various insects in the family Formicidae in the order Hymenoptera, typically living in large colonies composed almost entirely of flightless females.
CAN - To know how to; to be able to.
CAT - Any similar animal of the family Felidae, which includes lions, tigers, bobcats, etc.
CON - To study, especially in order to gain knowledge of.
NOT - Negates the meaning of the modified verb.
TAN - A symbol of the trigonometric function tangent.
TON - A unit of weight (mass) equal to 2240 pounds (a long ton) or 2000 pounds (a short ton) or 1000 kilograms (a metric ton).
COT - A symbol of the trigonometric function cotangent.
OAT - Widely cultivated cereal grass, typically Avena sativa.
TOT - A small child.
COAT - An outer garment covering the upper torso and arms.
TACO - A Mexican snack food; a small tortilla with some rice, beans, cheese, diced vegetables (usually tomatoes and lettuce, as served in the United States) and salsa.
TACT - The sense of touch; feeling.
CONTACT - The act of touching physically.