How to pronounce "halcyon"?

Merriam-Webster: http://www.merriam-webster.com/dictionary/halcyon

I've only ever heard it pronounced hal-see-uhn in English, and according to most dictionaries, it seems to be the only pronunciation option. It may have been anglicized from the Greek αλκυόνα, but it doesn't seem to have retained the 'k' pronunciation.

The IPA phonetic pronunciation is /ˈhælsiən/, which roughly translates to HAL-see-un or HAL-see-in, depending on your regional variation of schwa.

If IPA isn't your thing, Forvo is a great resource for audible pronunciation help.

Looks like I'm 2 years and 6 months late, but here you go: Halcyon is indeed "kingfisher," as per the other more learned respondents. Just found an interesting quote:

"This beautiful bird's floating nest was fabled to calm winds and seas while the bird sat. This occurring in winter gave rise to the expression 'halcyon days.' " -- Admiral William Smyth's Sailor's Word-book, 1867