Ancient
adverb, noun, の adjective
If you come to the party wearing something really, really old, everyone will know you're from ancient times (as if your wrinkles didn't give it away already, right?).
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
カッパは、日本古来のようかいです。
The kappa is an ancient Japanese yokai.
古来、この池は、「ワニカニの池」という名まえでしられていました。
In ancient times, this pond was known as "WaniKani Pond."
トイレは、古来から現代へと受け継がれてきた素晴らしい発明品だ。
The toilet is a wonderful invention that has been handed down since ancient times to the present-day.