A period of training and discernment for one seeking admission to a religious order. Like a postulant, Novices have not yet taken vows and are free to leave at any time. This is also a period of discernment for the order, and the Superior (leader) is also free to dismiss a novice if the arrangement is not discerned to be a good mutual fit.
From the ever-helpful Wikipedia:
After initial contact with the community, and usually a period of time as a postulant (a more or less formal period of candidacy for the novitiate), the person will be received as a novice in a ceremony that most often involves being clothed with the religious habit (traditional garb) of the particular religious community. The novice's habit is often slightly different from those of professed members of the order. For instance, in communities of women that wear a dark veil over the head, novices often wear a white one; among Franciscan communities of men, novices wear an additional shirt-like chest piece over the traditional Franciscan robe; Carthusian novices wear a dark cloak over the usual white habit; etc.Novices are not admitted to vows until they have successfully completed the prescribed period of training and proving, called the novitiate. This usually lasts one year, the minimum required by Canon Law, though in some orders and communities it is two. Novices typically have dormitories in separate areas within a monastery or community and are under the direct supervision of a novice master or novice mistress.
Even more helpful is this page on the stages of formation of religious life from the Dominican Sisters of Mary, Mother of the Eucharist. The above photo is also from their site showing a postulant, a novice and a fully-professed sister.
The place where novices live is also know as a novitiate.