any member of a class of words that typically can be combined with determiners to serve as the subject of a verb, can be interpreted as singular or plural, can be replaced with a pronoun, and refer to an entity, quality, state, action, or concept… See the full definition| www.merriam-webster.com
the process of becoming pregnant involving fertilization or implantation or both; embryo, fetus; beginning… See the full definition| www.merriam-webster.com