The term delineation is used in astrology in order to refer to the interpretation of an astrological chart.
The term is most commonly used to refer to the interpretation of a natal chart, although it can also be used to refer to the interpretation of other types of charts as well. For example, a delineation of a a horary chart would involve a discussion about the layout of the chart, as well the astrologer’s interpretation of the answer to the question, insomuch as the answer is sought to be derived from the chart cast for the moment of the question.
When an astrologer interprets a chart they are said to “delineate” the chart.
Usually a delineation of a chart is done by an astrologer, although technically since a delineation is just an interpretation of the significance of astrological placements, a delineation can be derived from other sources as well. For example, in modern times astrological reports that are generated by computers are sometimes referred to as “computerized delineations”. One might also read a list of delineations from a book, since there are a number of books which provide delineations or interpretations of astrological placements.