Comments for the name Hiroko

There are actually many meanings for this name (and Hiroko is fairly common in multiple generations).

Kanji for "hiro":
-wide/open/spacious (there are a couple kanji possibilities for this meaning)
-generous
-big sea

Other possibilities for girls using the "Hiro" kanji at the beginning:
Hiroe
Hiroka
Hiromi

Hiroko Haruna (known as Laura Haruna) is the name of a character in the anime series, "Tottoko Hamutaro" (Hamtaro). She's Hamtaro's owner.