a neighbor or someone living in the adjacent house

पड़ोसी

English Usage: "My nextdoor neighbor always waves at me."

Hindi Usage: "मेरा पड़ोसी हमेशा मुझे हाथ हिलाता है।"

located in the house or apartment next to yours

पास का

English Usage: "The nextdoor apartment is currently for rent."

Hindi Usage: "पड़ोसी अपार्टमेंट इस समय किराए पर है।"

in the direction of or at the adjacent house

पास में

English Usage: "She lives nextdoor to her best friend."

Hindi Usage: "वह अपने सबसे अच्छे दोस्त के पास में रहती है।"