GEAR!
Another word for "tie" that starts with the letter "g" is "girdle." A girdle can refer to a belt or a similar item used to fasten or secure clothing, serving a similar function to a tie in some contexts.
Another word for addition which starts with the letter N is New.
letter
Another word for water that starts with the letter 'O' is oxygen dihydrogen.
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Astonishing.
Atop.
advertise
Amazing
astamp
Orator is another word for speaker.
"Deceiver" is another word for liar that starts with the letter A.