Christmastide: Época de Natal. The season of Christmas, especially the festival celebrated from Christmas eve to the eve of Epiphany, January 5.

Epiphany: Epifânia. In many Christian churches, a yearly festival, held January 6, commemorating both the revealing of Jesus as the Christ to the Gentiles in the persons of the Magi and the baptism of Jesus; an appearance or manifestation of a god or other supernatural being. Also called "Twelfth Day" (12 noites após o Natal). A moment of sudden intuitive understanding; flash of insight. (Vivi algum tempo na Itália, na região do Vêneto, a poucos quilômetros de Veneza, em Oderzo. Lá, a Epifânia é uma festa de celebração da morte e renascimento da natureza, representada por uma bruxa boa [La Befana], que distribui doces para as crianças. As vitrines trazem diversas figuras de bruxas e as pessoas decoram suas casas com uma bruxa.)

Mistletoe: Visco. Às vezes confundida com o azevinho (holly). A semi parasitic green shrub with thick green leaves and waxy white berries used as Christmas decoration in English-speaking countries, where it is believed that it has the magical powers of granting the right to kiss anyone standing beneath it. The tradition in England is that, after every kiss, a berry is plucked from the twig and when the last berry is removed, the twig's powers are exhausted. The powers of American mistletoe last much longer. It is difficult to dissociate mistletoe from the act of kissing: "This pickle makes me pucker up more than a tree full of mistletoe." But during the holidays, avoid insults like: "I would sooner eat the mistletoe than kiss him." If someone rubs you the wrong way, rather than resort to crude language, in keeping with the holiday spirit, simply say: "As I walk away, kindly note the mistletoe attached to my coattail”.
Source: YourDictionary