The term daisho (kanji: 大小) means "big and small" in English. It is written だいしょう in hiragana. It may also be rendered in English as daishō or daishou. It's pronounced roughly like "die-show".
Besides referring to a pair of swords (typically a katanaKATANA 刀 "sword" learn more... and a shorter wakizashiWAKIZASHI 脇差 or 脇指 "medium-length sword" learn more...), it can refer to a large and small pair of tsuzumi drums. It also describes the waxing and waning of the moon. More generally, the word is used in the phrase daisho wo towazu (大小を問わず), which means regardless of size.