The root meaning of the third house is immediate environment. The most immediate environment is the home, in the specific sense of what the home environment is like as a whole, not the individuals of the family. What kind of energy is generally felt in the home, how do you react to it, is it quiet or is it noisy, do you have enough space for yourself, both physically and mentally. Basically all the things in the home that are picked up by your senses and influence your mood as well as general well being.
The immediate environment also includes the area right around your home, such as your neighbors. What kind of neighborhood would you prefer to live in? How do you interact with your neighbors? Extending the neighborhood idea, the immediate environment could be broadened to envelope the town as a whole. Which then brings into the 3rd house another meaning, and that is local travel. This could mean traveling for grocery shopping in your town, or traveling to the mall a few miles out, or even traveling to a neighboring state if it’s close enough that you could travel there often. The point is you are traveling to familiar places. So the neighborhood includes places and people that are familiar due to frequent interaction.
“Familiar people” includes siblings, who are the earliest familiar beings in the home (aside from parents), so siblings are another signification of the 3rd house. The sign on the cusp of the 3rd house, and planets, if any, in the house will suggest your relationship with siblings. (As an aside, Vedic or Indian astrology uses different houses for younger and elder siblings, but modern Western astrology lumps them all into the 3rd house. So if you have more than one sibling, you will need to tease apart all the qualities signified by the sign on the cusp and the planets in the house, into particulars that can be attributed to the individual siblings.)
The natural third house is in the sign of Gemini, which is associated with communication. Thus the 3rd house is seen for how a person communicates with others. So, speakers and writers have an emphasized 3rd house, such as a having a planet in the house that confers a powerful writing voice, or make for a prolific output. Such emphasis could be parlayed into employment or gig or influence: think of a salesperson (speaking and persuading day in and day out), a motivational speaker, a journalist, an author, a blogger, a social media influencer.
Stephen King (“America’s favorite writer”) has Virgo on the cusp of the 3rd house, with the Sun (in Virgo), Venus (in Libra), and Neptune (in Libra) placed there. Bruce Springsteen, whose songwriting conveys exuberant emotion and inspired directness, has Cancer on the cusp of the 3rd house, containing Mars and Pluto in Leo.
Media – newspapers, radio, television, podcasts, and various social media outlets – as source and disseminator of information belongs in the 3rd house. After hanging up his boots as quarterback of the Dallas Cowboys, Tony Romo found a successful new career as a football commentator in television. Can we see this in his horoscope via the 3rd house?
The 3rd house has no planets. Venus rules the 3rd house cusp of Taurus The ruler of the cusp of a house carries forward or owns the significations of the house, so you can think of Venus as the significator of communication (and all 3rd house matters) for this horoscope. Venus is tied to Neptune, which is a significator of television (imagery), through an opposition. Venus is in Mercury’s sign of Gemini, and is also sextile Mercury. Gemini as the sign of the natural 3rd house, and its ruler Mercury, both signify communication, so this Venus by the two-fold association with both is strongly indicative of communication. And Neptune itself is trine Mercury. The orb of the trine is a little wide at just over 12 degrees, but the pull of the Venus-Neptune opposition and the Venus-Mercury sextile put the trine very much into play. The sextile (creative/opportunistic) and trine (easy energy flow, natural talent) to Mercury from both ends of the Venus-Neptune opposition strongly reinforce the communication/TV theme, especially as a viable career option because Neptune is in the 10th house of career.
Look at the 3rd house in your own horoscope, and see what sign is on the cusp. How do the qualities of that sign resonate with how you react and manage your immediate environment: the general ambience in the house, the neighbors, your siblings.
If there are planets in the 3rd house, how do their qualities influence your mode of communication, your speech and writing, how you listen to others, how you receive and process information coming at you? With Neptune in the 3rd house, you may be very receptive to your environment, picking up on all kinds of stuff in the air, highly sensitive to non-verbal cues. With Saturn, you might be very discerning about what to pay attention to and what to ignore, careful to choose your words, mindful to verify information coming your way for reliability.
Also look at the ruler of the 3rd house cusp, and see how it carries forward and owns the significations of the 3rd house via its aspects to other planets. For instance, if the 3rd house cusp is in Leo, then the Sun would serve as a proxy for 3rd house significations. Look at the aspects made by the Sun. If it were, say, in a square aspect to Saturn, then it would be similar to having Saturn in the 3rd house.
Communication and perception, and the mindset as a whole, play a crucial part in how we deal with our immediate world, and it is so very important that we understand the condition of the 3rd house in our horoscope.