Fern comes from the Old English fearn — the leafy non-flowering plant that grows in forests and damp places. Ferns are among the oldest plant lineages on Earth, predating flowering plants by hundreds of millions of years.
Fern was popular in the early 20th century as part of the wave of nature-word names. E. B. Today Fern is rising fast as part of the broader return of botanical names.
Fern 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 Fern reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.