"CH" is the only valid Scrabble word starting with C.
There's the proper name Cy, but most two-letter words are abbreviations.
ca -- circa, calcium, California
cb -- Citizen's Band
cc -- carbon copy, cubic centimeter, Cape Cod
cd -- compact disc, cadmium
ce -- cerium
cf -- Californium
cg -- centigram, Coast Guard
ch -- church, clearing house, custom house
ci -- cirrus, Curie, Channel Islands
cj -- Chief Justice
cl -- centiliter, chlorine
cm -- centimeter, curium
co -- cobalt, Colorado, company, conscientious objector
cp -- Cerebral Palsy, candlepower
cr -- credit, chromium
cs -- cesium, Civil Service
ct -- Connecticut
cu -- copper
cv -- curriculum vitae
cy -- calendar year
ClimatesCommuterComputerConstant
Candlelit.
Long words starting with the letter c compliment confidence congratulate consciousness considerate cooperate contribute constructive courteous
ceasechafechasechidechimechivechokechorechosechuteclonecloseclovecratecravecrimecrudecursecurvecycle
There are no 2-letter English words with C.
choice
ClimatesCommuterComputerConstant
Candlelit.
Long words starting with the letter c compliment confidence congratulate consciousness considerate cooperate contribute constructive courteous
ceasechafechasechidechimechivechokechorechosechuteclonecloseclovecratecravecrimecrudecursecurvecycle
There are no 2-letter English words with C.
coffles
crows, carts
CalcuttaCambodiacamelliaCanberraCarolinaCasanovacharismachickpeaChippewacinchonaColombiaColumbiacontinuacredenzaor criteria.
CabbageCouragecapturecarnagecensurechemiseclimateclosurecombinecomparecompilecomputeconcavecondolecondoneconfineconfuseconjurecommodeconnoteconsoleconsumeconvenecorrodecottagecremate
catalytic converter
Five letter words starting with C and ending with X are calyx and codex.