a Classical Japanese adjective with ク活用 (ku-katsuyō, “ku-inflection”)

safety first

monetization

to monetize

first / number one / primary

ordinal marker, often with affix 号

one day

one, 1 / the first in order, foremost / the beginning / the best / a kind of; one of something / (card games) an ace / unity / the bottom string of a shamisen or other Japanese musical instrument

each person

first discoverer (used especially in reference to the discovery of a dead body)