David Vašek (asker) Sep 25, 2015:

Zajímavé je, že angličtina patrně nemá přesný a neměnný ekvivalent tohoto významu (kulaté narozeniny), natož jednoslovný. V tomhle má čeština navrch! :-)

Stuart Hoskins Sep 25, 2015:

Hannah's deleted (but important) comment "Milestone birthdays also include those that are not "kulatiny" such as 16 (Sweet Sixteen) 13 (Jewish religion), 18 or 21 etc. So - in this particular context, the big 0 fits well, I think." Absolutely, in this context it is "Big Five-Oh". However, if it had been the guy's 30th, I would have hesitated with "Big Three-Oh" (Doesn't seem that big to me). How do we refer to a 30th, perhaps even 40th, birthday (I don't know)?

Roni_S Sep 24, 2015:

No reason you couldn't say "This guy (dude, whatever) who recently celebrated the big five-oh...."

David Vašek (asker) Sep 24, 2015:

kontext Chlapík, který oslavil své minulé kulatiny (= 50 let) ve velkém stylu...., si prý (nyní při šedesátinách) raději odpočine na své lodi.