hi–fi 
/ˈhaɪˈfaɪ/ noun
plural hi–fis /ˈhaɪˈfaɪ/ noun 1 [noncount] : high fidelity 2 [count] somewhat old-fashioned : a piece of electronic equipment for reproducing sound in a clear and accurate way
▪ We bought a hi-fi for the bedroom.
▪ We bought a hi-fi for the bedroom.
— hi–fi adjective
▪ hi-fi sound reproduction ▪ a hi-fi system ▪ hi-fi equipment
▪ hi-fi sound reproduction ▪ a hi-fi system ▪ hi-fi equipment
