Green’s Dictionary of Slang

1. (US) emotionally overcome, thrilled.

2021

J. Ellroy Widespread Panic 89: She flashed her crooked teeth. I went all woo-woo.

2. pertaining to various ‘new age’ therapies, e.g. mindfulness, wellness.

2008		J. Macdonald Baby Doctors [ebook] ‘[L]et me tell you, she knows a thing or two about woo-woo medicine.’ Sarah shot Rose a glance. ‘A focus on prevention and wellbeing rather than disease is not woo-woo medicine’.
2021		Betoota-isms 73: ‘As part of my worker’s compo insurance, I’ve gotta go visit the Scientologist [i.e. chiropractor] and get treated with that woo woo medicine’.