"du" isn't an Irish word, however "dú" is. "dú" is a prefix meaning black / dark
It has no meaning: it's not a Gaelic word.
Taylor is not a Gaelic word and has no meaning in Gaelic.
It has no meaning in Gaelic; it's not a Gaelic name.
The Irish surname O'Dea, was shortened to Dea/Day/Daw/Dee. Dee could also be the Welsh "Du" (pronounced dee) which means "black".
The word 'bassett' is not a Gaelic word, and therefore has no meaning in Gaelic.
It would be 'fiach bán' in Irish; in Scottish Gaelic: ?
"Colin" isn't a Gaelic word and therefore doesn't have a meaning in Gaelic.
Cassandra does not have meaning in Gaelic because it's not Gaelic. It's a name of Greek origin possibly meaning 'shining upon man'.
Lexiology.com Dictionary http://www.lexiology.com/meaning/gaelic
'Heath' is an English word with no meaning in Gaelic.
The word 'luck' is in English not Irish Gaelic.
'Nah' doesn't appear to be Gaelic.