“AITCH” is a valid word. — 10 points Scrabble

chatan informal conversation
itcha contagious skin infection caused by the itch mite; characterized by persistent itching and skin irritation
chita dismissive term for a girl who is immature or who lacks respect
chia
tachmeasuring instrument for indicating speed of rotation

hit(baseball) a successful stroke in an athletic contest (especially in baseball)
acta legal document codifying the result of deliberations of a committee or society or legislative body
catfeline mammal usually having thick soft fur and no ability to roar: domestic cats; wildcats
hatheaddress that protects the head from bad weather; has shaped crown and usually a brim
chithe circulating life energy that in Chinese philosophy is thought to be inherent in all things; in traditional Chinese medicine the balance of negative and positive forms in the body is believed to be essential for good health
ich
tica local and habitual twitching especially in the face
hic
ait

itthe branch of engineering that deals with the use of computers and telecommunications to retrieve and store and transmit information
ata highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium
hian expression of greeting
ah
ha(astronomy) the angular distance of a celestial point measured westward along the celestial equator from the zenith crossing; the right ascension for an observer at a particular location and time of day
taa hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite
aian agency of the United States Army responsible for providing timely and relevant and accurate and synchronized intelligence to tactical and operational and strategic level commanders
tia light strong grey lustrous corrosion-resistant metallic element used in strong lightweight alloys (as for airplane parts); the main sources are rutile and ilmenite

AITCH