If it's a cryptic crossword, the answer is "ess," the first letter (head) of "state."
As. The shortest word beginning with the letter a is "a"
state, steep, stiff, stoop, study, style
The word is :versevaultvaluevalvevideovenueviperviralvitalvotervaporvocal
Burr
A four letter word beginning with C and ending with X is crux.
A seven letter word beginning with C with a the fourth letter C is cracker.
Some four letter words beginning with TO are:toadtoiltoldtolltooktooltoottorntosstorttourtown
Some 'qu' words beginning with the letter 'I' are:inquestinquiryinequityinquisitiveIroquois
ignoredillicitimpaledimpoundimpressimmoralinheritinclineindentsingrateinsultsingestsingrowninvalidinsistsinjectsinvents
allotmentamendmentargumentsassigningattachingattributeavailable
Atom,
a synonym for slow beginning with the letter r is retard