wassail

[wos-uh l, -eyl, was-, wo-seyl] /ˈwɒs əl, -eɪl, ˈwæs-, wɒˈseɪl/
noun
1.
a salutation wishing health to a person, used in England in early times when presenting a cup of drink or when drinking to the person.
2.
a festivity or revel with drinking of healths.
3.
liquor for drinking and wishing health to others on festive occasions, especially spiced ale, as on Christmas Eve and Twelfth-night.
4.
Archaic. a song sung in wassailing.
verb (used without object)
5.
to revel with drinking.
verb (used with object)
6.
to drink to the health or success of; toast.
Origin
1175-1225; Middle English was-hail, equivalent to was be (Old English wæs, variant of wes, imperative of wesan to be; akin to was) + hail hale1, in good health (< Old Norse heill hale); replacing Old English wæs hāl be hale or whole. See whole, heal
Related forms
wassailer, noun
British Dictionary definitions for wassail

wassail

/ˈwɒseɪl/
noun
1.
(formerly) a toast or salutation made to a person at festivities
2.
a festivity when much drinking takes place
3.
alcoholic drink drunk at such a festivity, esp spiced beer or mulled wine
4.
the singing of Christmas carols, going from house to house
5.
(archaic) a drinking song
verb
6.
to drink the health of (a person) at a wassail
7.
(intransitive) to go from house to house singing carols at Christmas
Derived Forms
wassailer, noun
Word Origin
C13: from Old Norse ves heill be in good health; related to Old English wes hāl; see hale1
Word Origin and History for wassail

mid-12c., from Old Norse ves heill "be healthy," a salutation, from ves, imperative of vesa "to be" (see was) + heill "healthy" (see health). Use as a drinking phrase appears to have arisen among Danes in England and spread to native inhabitants. A similar formation appears in Old English wes þu hal, but this is not recorded as a drinking salutation. Sense extended c.1300 to "liquor in which healths were drunk," especially spiced ale used in Christmas Eve celebrations. Meaning "a carousal, reveling" first attested c.1600. Wassailing "custom of going caroling house to house at Christmas time" is recorded from 1742.