noun-modifying (irregular)
Old attributive form of 古い (ふるい). Used prenominally in classical or literary contexts, often in fixed expressions like 古き良き時代 (the good old days). Not used in modern conversational Japanese.
I feel nostalgic for the good old days.
Old traditions remain in this town.
Archaic prenominal form of 古い; mainly encountered in set phrases, literary language, or fixed expressions.
Archaic attributive form of the adjective 古い (ふるい). The -ki ending is the classical Japanese attributive form for -i adjectives.