n. [ Christ + mass. ] An annual church festival (December 25) and in some States a legal holiday, in memory of the birth of Christ, often celebrated by a particular church service, and also by special gifts, greetings, and hospitality. [ 1913 Webster ]

Christmas box. (a) A box in which presents are deposited at Christmas. (b) A present or small gratuity given to young people and servants at Christmas; a Christmas gift. --
Christmas carol, a carol sung at, or suitable for, Christmas. --
Christmas day. Same as Christmas. --
Christmas eve, the evening before Christmas. --
Christmas fern (Bot.), an evergreen North American fern (Aspidium acrostichoides), which is much used for decoration in winter. --
Christmas flower,
Christmas rose, the black hellebore, a poisonous plant of the buttercup family, which in Southern Europe often produces beautiful roselike flowers midwinter. --
Christmas tree, a small evergreen tree, set up indoors, to be decorated with bonbons, presents, etc., and illuminated on Christmas eve. [ 1913 Webster ]

n. 1. a spiny evergreen shrub of southeastern U. S. (Lycium carolinianum) having spreading branches with usually blue or mauve flowers and red berries.
Syn. -- Christmas berry, Lycium carolinianum. [ WordNet 1.5 ]

2. an ornamental evergreen treelike shrub of US Pacific coast (Photinia arbutifolia) having large white flowers and red berrylike fruits; often placed in genus Photinia.
Syn. -- toyon, tollon, Christmas berry, Heteromeles arbutifolia, Photinia arbutifolia. [ WordNet 1.5 ]

n. [ Christmas + tide time. ] The season of Christmas. [ 1913 Webster ]