words I know the meaning of but use in place of other words anyway:

ampersand
is actually a: noun
and it means:a punctuation mark (&) used to represent conjunction (and)
but I use it as a: exclamatory vulgarity
like this: "That guy is such an ampersand!"

coagulate
is actually a: adjective
and it means: 1. transformed from a liquid into a soft semisolid or solid mass; "coagulated blood"; "curdled milk"; "grumous blood"
but I use it as a: verb
like this: "stop bugging me or i'm going to fucking coagulate you."

atrophy
is actually a: noun
and it means:Pathology A wasting or decrease in size of a body organ, tissue, or part owing to disease, injury, or lack of use
but I use it as a: verb
like this: "I can't handle the cold- my hands atrophy."