Spellbound means so held by something that you cannot look away. Held spellbound, a spellbound audience, watched spellbound.
It is nearly always used of an audience and is the highest ordinary compliment to a performer. The image is literal: somebody spellbound is bound by a spell and cannot move.
1adjectivespellboundSo held by something that you cannot look away.
“The children listened spellbound as their grandfather told the ghost story.”
spellbound is a state.
Spell plus bound, from the past participle of bind.
From spell + bound.
Etymology from Wiktionary, CC BY-SA