(obsolete) Short for ポートランド市 (Pōtorando-shi, “Portland (a city in Oregon, United States)”).

city

to live in, to inhabit, to abide at, to dwell at

ancient times, a very long time ago

(nonstandard) The katakana syllable コ゚ (ngo). It's equivalent in hiragana is こ゚ (ngo)

Short for 児童ポルノ.

once (in the indeterminate past)

the past, old times / ancient

olden days; former

The katakana syllable ポ (po). Its equivalent in hiragana is ぽ (po).