honeymoon

Concise Oxford English Dictionary © 2008 Oxford University Press:
honeymoon/ˈhʌnimuːn/

▶noun

• 1 a holiday taken by a newly married couple.

• 2 an initial period of enthusiasm or goodwill.

▶verb spend a honeymoon.

– derivatives
honeymooner noun.

– origin C16: from honey + moon (orig. referring to affection waning like the moon, later denoting the first month after marriage).