What does fluorescein mean?

fluorescein (noun): Any of a class of yellow xanthene dyes which are visible when highly diluted; used forensically to detect traces of blood, and in analytical chemistry as an indicator in silver nitrate titrations As a hashtag, #fluorescein carries this topic across social platforms.

How popular is #fluorescein?

#fluorescein has no measured public activity on the open social web in the last 7 days. It is currently wide open.

What hashtags are related to #fluorescein?

No related hashtags with measured usage were found for #fluorescein.

How much does it cost to own #fluorescein?

#fluorescein is available as a #name from $10.85 per year. You can claim it by card at https://hashtag.orghttps://hashtag.space/checkout/portal-name?name=fluorescein or with tokens on hashtag.space at https://hashtag.space/#fluorescein.

#fluorescein

Name: #fluorescein — a #name on hashtag.org
Brand: hashtag.org
Price: 10.85 USD
Availability: InStock

Live, measured metrics for the hashtag #fluorescein from the open social web. Every number carries a named source and the time it was fetched. Nothing is estimated.

hashtag.org network · sponsored

Own #fluorescein

This #name is available to claim. It becomes your portal on the open agent web: this very page, a keyword you rank for by an open public stake, and a verifiable identity for AI agents. Nobody else sells a page like this for every #name.

$10.85/ year · 11-character #name

Claim #fluorescein — $10.85/yr→Buy on hashtag.space (web3)

card via hashtag.org · tokens via hashtag.space

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Uses / 7 days

Mastodon

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Accounts / 7 days

Mastodon

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Day-by-day usage

measured · mastodon.social (Mastodon public tags API) · fetched 2026-11-09 03:40 UTC

No measured public usage for #fluorescein in the last 7 days. That is a real result, and a good one to know: this hashtag is wide open right now. We show a dash before we ever show a made-up number. Browse the trending index for tags with live measurements.

Related hashtags

measured · mastodon.social (Mastodon public search API) · fetched 2026-11-09 03:40 UTC

No related tags with measured usage found for #fluorescein.

Live pulse

measured · Mastodon tag timeline · fetched 2026-11-09 03:40 UTC

No recent public posts found for #fluorescein on Mastodon. Nothing measured, so nothing shown.

What “fluorescein” means

Wiktionary · Wikipedia

fluorescein

nounAny of a class of yellow xanthene dyes which are visible when highly diluted; used forensically to detect traces of blood, and in analytical chemistry as an indicator in silver nitrate titrations

Full entry on Wiktionary →

Fluorescein is an organic compound and dye based on the xanthene tricyclic structural motif, formally belonging to triarylmethane dyes family. It is available as a dark orange/red powder, slightly soluble in water and alcohol. It is used as a fluorescent tracer in many applications.

“Fluorescein” on Wikipedia (CC BY-SA) →

#fluorescein across platforms

every network with a public tag surface

Follow #fluorescein straight to each platform’s own tag page. Where a platform publishes open data we measure it above; the rest lock their numbers behind paid APIs, so we link rather than guess.

X (Twitter) ↗Instagram ↗TikTok ↗Facebook ↗LinkedIn ↗YouTube ↗Threads ↗Bluesky ↗Mastodon ↗Reddit ↗Pinterest ↗Tumblr ↗

Every number above is measured from a named public API at the shown fetch time. Nothing is estimated or extrapolated. Platforms that lock their data behind paid APIs are not shown. Agents: the same numbers, as JSON, at /api/hashtags/fluorescein