Metis (Μῆτις) is the Greek word for "cunning wisdom, skill, craft." The Greek Titaness of wise counsel, planning, cunning, and craftiness — Zeus's first wife. An oracle prophesied that any son she bore would be greater than his father, so Zeus swallowed her whole while she was pregnant — Athena was later born fully grown and armored from Zeus's forehead, after Hephaestus split it open with an axe. Metis remains inside Zeus, serving as his counsel — Hesiod tells us that this is the source of Zeus's wisdom.
Metis does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Metis reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.