How to interpret the result
In a constructed chart with a Taurus Lagna, Moon in Virgo, Venus in Gemini and Mars in Leo, Mars is in house 4 from the Lagna and house 12 from the Moon, both triggered, but house 3 from Venus, not triggered. Leo offers no cancellation, so the page says the formation remains under this rule, a statement about a chart pattern and nothing about any relationship.
Why it matters
Manglik, also called Kuja Dosha, is checked mostly in traditional matchmaking, and schools disagree on which references count, whether house 2 belongs and which exceptions apply. With six of twelve houses qualifying from each of three references, a large share of charts trigger at least one count, so careful readers treat the label as common rather than alarming.
Traditional meaning
Mangala, the Sanskrit name for Mars, stands in the tradition for drive, heat and assertiveness, and the listed houses are ones tradition ties to home, family and partnership. Regional sources list many more cancellations than this one.
Reflection use
Note which references triggered and how close your birth time is to a Lagna change, since that count flips most easily. If the label comes up in family conversation, bring the three lines and the method name so the discussion stays on what was checked.