Yes, UNCTION is a Scrabble word!

Letter values in Scrabble US: U 1, N 1, C 3, T 1, I 1, O 1, N 1.

Is it a valid word?

UNCTION is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

excessive but superficial compliments given with affected charm
smug self-serving earnestness
semisolid preparation (usually containing a medicine) applied externally as a remedy or for soothing an irritation
anointing as part of a religious ceremony or healing ritual