The term gokaden (kanji: 五箇伝 五ヶ伝) means "the five traditions" in English. It is written ごかでん in hiragana. It's pronounced roughly like "go-kah-den".
The gokaden refers both to the five major schools of sword making as well as the regions those schools are associated with.
伝, when pronounced as den (the Chinese reading), is not used in everyday Japanese. However, when pronounced as tsute (the Japanese reading), it is sometimes employed in conversation. It means “communication” as well as “connections” (e.g., job connections).
ヶ, simply the small version of the katakana letter ケ (ke), is an abbreviation of 箇. Both are used here as counter suffixes: that is, suffixes that keep count of something (i.e., the number of traditions, which is five).