dinkum
adjective
[ ˈdɪŋkəm ]
• (of an article or person) genuine, honest, true.
• "a real dinkum bloke"
dinkum
adverb
• really, truly, honestly.
Origin:
late 19th century: of unknown origin.
fair dinkum
• used to emphasize or seek confirmation of the genuineness or truth of something.
• "Eric and his assistant are fair dinkum magicians"