They are among the most commonly identified sources of spiritual meaning. Astrology, tarot, religious ritual, prayer, the Bible, and the I-Ching are some of the tools people have employed in their search for spiritual meaning. Meaning cannot be found lying around like rocks in a meadow.
Meaning is a state of mind in about the same way that running is a state of water.
Attempting to live within the limitations of language, we could try thinking of meaning as something that is always created as we go along. Birth is a creative process, but it is not consciously directed. Meaning, like a baby, grows into being from a deep, mysterious, unconscious source. Some people might be satisfied with these answers, but I am not. Given the painfulness of the event it might be perceived more as rape than love-making, but in any case the result must be that I become pregnant with meaning, and when ready I must give birth.