Dysprosium is element number 66, with the symbol Dy. Its name comes from the Greek for “hard to get at.”
Atomic number 66162.5
DyDysprosiumジスプロシウム (jisupuroshiumu)
Symbol
Dy
Atomic weight
162.5
Place in the table
Period 6 · Lanthanoids
Atomic weight from the Chemical Society of Japan, “Table of Standard Atomic Weights with Four Significant Figures (2026)”.
Hard to find
Dysprosium was discovered in 1886. Because its discovery was so difficult, it was named “hard to get at.”
Where it sits on the table
The fifteen elements from lanthanum to lutetium are called the lanthanoids. On the Room of the Elements table they are in the upper of the two rows set apart at the bottom.
Think about it
Q1What do you think of naming an element after how hard it was to find?
Q2Why might the lanthanoids have been hard to tell apart?
Q3Are there other elements whose names reflect a difficult discovery?
There is no single right answer. Talking it over with someone at home is a good way to learn.
Did you know? — Names about being hard to find include dysprosium (hard to get at), lanthanum (lying hidden) and krypton (hidden).