You are deluding yourself.
The boy was sure the girl liked him, but he was deluded. the previous answer was wrong: "Some chemicals have to be deluded before using them." The word you are thinking of is diluted!
I am not writing a sentence using that word.
I can give you a sentence using the word galaxy.
a sentence using the word endotracheal
This is a sentence using the word aviator.
The noun forms of the verb to delude are deluder, delusion and the gerund, deluding.
I am saying a sentence using the word collagen.
This is a sentence using the word monomer. :P
this is a sentence using the word armchair.
Need a sentence using the word crater?
Please type a sentence using the word assertion.
I can write a sentence using the word scorn!