fanatic

Synonyms:

enthusiast, zealot, extremist, devotee, aficionado

Definition:

a person who is extremely interested in something, to a degree that some people find unreasonable

Grammar:

[ noun, [ C ]]

Examples:

( short ) Sports fanatic

( common ) an absolute fanatic about [something]

( situation ) a fitness/sports fanatic

( pickup line ) Are you a Taylor Swift fanatic? Because I am 'Fanatic' about getting to know you.