無

open city; defenseless city

unpaid doctor

mutual aid or credit finance company

person who has not won any major awards or titles despite being the best in a particular field; uncrowned king

person who wields power without holding an official rank or title

journalist (esp. newspaper journalist)

Buddhism

the one-character reply ("no") offered by Zhaozhou to the question "Does a dog have Buddha nature?"

open freight car

unauthorized reproduction; unauthorised reproduction; unauthorized copying; unauthorised copying

virtueless

Archaic

poor

not submitted to the selecting committee

non-sectarian

unfiltered (alcohol)

irreligion; atheism

Abbreviation

infinite

incumbent member (or candidate) unaffiliated with a party

Yojijukugo

abandoning artifice and just being oneself; doing nothing and taking things as they come

Buddhism

unconditioned nature; unconditioned spontaneity

Chemistry

anhydrous

waterless; requiring no water

nonstop flight

unemployed person

normal temperature

tomb of someone with no relatives to mourn their death

Architecture

(openable) panel in a door

Nouns which may take the genitive case particle 'no'

having no wife; being single; being unmarried

unmarried man

idle and incompetent; accomplishing nothing significant nor being capable of doing so; lacking the talent to do anything but idle away one's time

Mathematics

infinite series

free of artificial colors; coloring-free