ACT - Something done, a deed.
BAT - Any of the small, nocturnal, flying mammals of the order Chiroptera, which navigate by means of echolocation. They look like a mouse with membranous wings extending from the forelimbs to the hind limbs or tail. Altogether, there are about 1,000 bat species in the world.
BUT - Outside of.
CAB - A taxi; a taxicab.
CAT - Any similar animal of the family Felidae, which includes lions, tigers, bobcats, etc.
CUB - A young fox.
CUT - Having been cut.
TAB - A small flap or strip of material attached to something, for holding, manipulation, identification, etc.
TUB - A flat-bottomed vessel, of width similar to or greater than its height, used for storing or packing things, or for washing things in.
TAU - The name of the letter T/τ in the Greek, Hebrew and ancient Semitic alphabets, being the nineteenth letter of the Classical and Modern Greek, the twentieth letter of Old and Ancient Greek.
BACK - Near the rear.
BUCK - A male deer, antelope, sheep, goat, rabbit, hare, and sometimes the male of other animals such as the ferret and shad.
TACK - A small nail with a flat head.
TUCK - To fit neatly.
TUBA - A large brass musical instrument, usually in the bass range, played through a vibration of the lips upon the mouthpiece and fingering of the keys.
ABUT - To lean against on one end; to end on, of a part of a building or wall.
CUTBACK - A reduction in an existing program of some sort.