Meanings according to Rider-Waite:
ASTROLOGICAL SIGNIFICANCE: The Sun in Taurus as a symbol of love of property, sensual joy, and a businesslike approach.
KNIGHT OF DISKS The Knight of Disks personifies the masculine side of the element of Earth. Thus, he embodies our striving to possess property, to be confident in the future and in real values, to be at peace with surrounding reality. For him, what matters most are deeds, not words, dreams, or good intentions. This is our striving for the solidity and reliability of being, for the possibility of constantly turning to that which is well known. At the same time, the Knight of Disks is distinguished by good intuition, an instinct that allows him to discern what is real and what is not, which undertaking is worth pursuing and which is not worth taking up at all, and what the result will be. Moreover, he has an excellent sense of timing: he understands that true values "ripen" slowly, and he knows how to wait. He is patient and does not acknowledge haste. In addition, he expresses our joy of life, love of amusement and pleasure, as well as carnal sensuality. But he has his shadow side as well: insatiable lust, hardened mercantilism, or indolent idleness — that very same "Oblomov within us" of whom I. Goncharov wrote so remarkably.
From the book: Hajo Banzhaf. THE TAROT HANDBOOK. Translated from the German by E. Kolesov. Publisher: Center for Astrological Research, 1999.
KING OF PENTACLES A person expressing his intentions in material form, embodying his convictions in something concrete, material. This includes concrete assistance. Provider for the family, benefactor. A trap. All attention given only to the material.
UPRIGHT POSITION Astrological equivalents: Taurus, Virgo, Capricorn, Mercury, Saturn, the Second House. The KING OF PENTACLES symbolizes an experienced and successful leader who has considerable life experience behind him. This is a firm man, with character, at times abrupt. At the same time, he is not lacking in refinement and is not a stranger to the spiritual. This is a man possessed of a brilliant mind. A good businessman, or else a brilliant specialist in the exact sciences. He can be a reliable friend, but his mind is cold. He can advise, but not sympathize (for the latter, one is better off turning to the KING OF CUPS). In marriage he is a reliable partner, although he is inclined to regard marriage as a form of contract that must be steadily adhered to. One cannot say that he is a faithful husband, since we have raised the subject of marriage. He is simply a person who clearly understands the difference between love, marriage, and sex, and does not mix them all into one heap. In business he is accompanied by good fortune, though he owes the latter rather to his intellect than to his courtesy. This person has an excellent feel for the present-day market and knows "which horse to bet on." Poverty does not threaten him. The ability to make money is in his blood; most likely, at present he possesses substantial property. REVERSED POSITION Astrological equivalents: the same as in the upright card, but the influence of Saturn is expressed more strongly, and instead of the Second House, the Eighth is engaged. One may say that in the reversed KING OF PENTACLES there is present a mixed influence of the signs of Gemini and Capricorn. The combination of these in astrology is considered unstable, conditioning the alternating fortunes through which a person is compelled to pass on his life's path, which also corresponds in no small measure to the character of the KING OF PENTACLES. The type of a corrupt politician or businessman who uses dirty means to achieve his ends. The reversed KING OF PENTACLES is treacherous, greedy; he cannot be trusted in anything. He has "two tongues." Sometimes this card can indicate a malicious old man who has not fallen into senility but has directed all his life experience and intellect toward his egotistical ends. The reversed KING OF PENTACLES is always associated with danger, with walking along the edge. Moreover, either he himself is the source of the latter, or he is forced to encounter it by virtue of his activity.
If the card signifies an action. A. Upright card The situation expressed by the subsequent cards may signify the beginning of a process born of the current process — that is, a filial process. Since PENTACLES are an "earthbound" suit, the situation described may be connected with conception, with origination. And this is not necessarily the conception of a child (although we shall not exclude such a variant); it may be the origination of anything whatsoever on the physical level, characterized by the fact that it will to a certain degree reflect its progenitor, having inherited his most characteristic features.
B. Reversed card The card will speak rather of the prematurity or barrenness of the situation expressed by the subsequent cards.