Upward is preferred in American usage.
Difference between Unwanted and Unwonted
Unwanted means not wanted. Occasionally we experience unwanted e-mails and phone calls. Unwonted means out of the ordinary or unusual. At the party, the children were in an unwonted state of excitement when they learned a clown was coming.
Difference between Unsoluble and Unsolvable
Both words mean not easily solved. The corporation continues to have unsoluble (or unsolvable) quality problems. Note: Unsoluble can also mean that something is not soluble in liquid.
Difference between Unequivocably and Unequivocally
Unequivocably is not a word.
Difference between Undoubtably and Undoubtedly
Undoubtably is not a word.
Difference between Undo and Undue
Undo means to reverse something. It will take much rain to undo the damage caused by the drought. Undue means inappropriate or excessive. They should be quiet and refrain from any undue criticism.
Difference between Understated and Unstated
Understated means said in restrained terms or done in a restrained manner. The company praised the product but understated its deficiencies. Unstated means unsaid. They followed unstated rules of conduct and dress.
Difference between Under way and Underway
Either spelling is acceptable.
Difference between Unconscience and Unconscious
Unconscious is the correct word, menas in a state like sleep because of an injury or illness, and not able to use your senses. Unconscience is not a word. By the time ambulancemen arrived he was unconscious.
Difference between Uncharted territory and Unchartered territory
Uncharted territory is the correct phrase.
Unbelievable
This is a much overused word. It actually means too improbable to believe rather than its common misuse of good. The festival offers good (not unbelievable) apple pies every fall. To them, the UFO story of Roswell, New Mexico is unbelievable.
Difference between Unbeknown and Unbeknownst
Either spelling is acceptable.