деся́ток

fairly common #3309B2

nounmasculineinanimatecountable

1.
ten, set of ten
Купи́ деся́ток яи́ц.
Buy ten eggs.
Common in shopping contexts: eggs, buns, etc. are counted in tens.
2.
dozens, scores, tens
На пло́щади бы́ли деся́тки люде́й.
There were dozens of people in the square.
Only in the plural десятки.
3.
decade, ten years
Ему́ пошёл пя́тый деся́ток.
He has turned forty.
Often of age: пошёл пятый десяток = he is over forty.

Examples

Интересно, почему яйца продаю́т деся́тками?
I wonder why eggs are sold by the dozen.
Писатель, исписывавший десятки листов за ночь, устал к утру.
The writer, filling dozens of sheets during the night, was tired by morning.
Ей в э́то вре́мя никак не мог быть тре́тий деся́ток.
She can't have been in her twenties at that time.
Этот сказочник придумал десятки волшебных историй.
This storyteller came up with dozens of magical tales.
Трое поги́бли, деся́тки други́х получи́ли ране́ния.
Three people died. Dozens more were wounded.
Офицер, завербовавший десятки добровольцев, получил награду
The officer who recruited dozens of volunteers received an award.
Этот схоласт написал десятки трудов о логике.
This scholastic wrote dozens of treatises on logic.
В параде участвовали десятки конников в форме.
Dozens of horsemen in uniform took part in the parade.