ARE - Second-person singular simple present tense of be.
ART - Human effort to imitate, supplement, alter, or counteract the work of nature.
EAR - The organ of hearing, consisting of the pinna, auditory canal, eardrum, malleus, incus, stapes and cochlea.
ERA - A time period of indeterminate length, generally more than one year.
RAT - A medium-sized rodent belonging to the genus Rattus.
RUT - Sexual desire or oestrus of cattle, and various other mammals.
TAR - A black, oily, sticky, viscous substance, consisting mainly of hydrocarbons derived from organic materials such as wood, peat, or coal.
RUE - Repentance, regret.
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.
RATE - A wage calculated in relation to a unit of time.
TART - Sharp to the taste; acid; sour.
TEAR - To rend (a solid material) by holding or restraining in two places and pulling apart, whether intentionally or not; to destroy or separate.
TRUE - Conforming to the actual state of reality or fact; factually correct.
TAUT - Tight; under tension, as in a rope or bow string.
QUART - A unit of liquid capacity equal to two pints; one-fourth (quarter) of a gallon. Equivalent to 1.136 liters in the UK and 0.946 liter (liquid quart) or 1.101 liters (dry quart) in the U.S.
TREAT - An entertainment, outing, or other indulgence provided by someone for the enjoyment of others.
QUARTET - A music composition in four parts, each performed by a single voice or instrument.