What does "atomic number 51" mean?

a metallic element having four allotropic forms; used in a wide variety of alloys; found in stibnite

What is a synonym for "atomic number 51"?

Common synonyms include: antimony, sb.

Rare ·Advanced level

Noun

1
a metallic element having four allotropic forms; used in a wide variety of alloys; found in stibnite wordnet