Answer:

oooh

Answer	Crossword Clue
OOOH	2000 De La Soul single curiously punctuated with a period
OOOH	Pyrotechnics reaction
OOOH	"I'm really impressed!"

OOOH	Squeal of delight
OOOH	Fireworks reaction
OOOH	Repeated interjection in the Rolling Stones' "Miss You"
OOOH	"How exciting!"
OOOH	... a circusgoer
OOOH	Circusgoer's exclamation
OOOH	Cry of delight
OOOH	"Aren't you special!"

OOOH	"Color me impressed!"
OOOH	"So nice!"
OOOH	Sound of delight
OOOH	"I'm intrigued!"
OOOH	"You're gonna get in trou-ble!"
OOOH	"Aaah" companion
OOOH	Sound of joy