Heroine – l'héroïne
(Pronounced ay-ru-een)
To remember that Heroine is pronounced ay-ru-een (héroïne) in French, use the following mnemonic:
The heroine discovered her house had become a ruin (héroïne.)

NOTE:
Héroïne is feminine, but as the "H" is silent it's treated as though it begins with a vowel, so it's l'héroïne. Imagine the Labrador is the heroine rescuing a cat stuck in a tree.

Examples of héroïne (heroine) in a sentence
Elle est la véritable héroïne de cette histoire.
(She is the true heroine of this story.)
L'héroïne du roman surmonte toutes les épreuves.
(The heroine of the novel overcomes all trials.)
Une jeune héroïne courageuse a sauvé le chat.
(A brave young heroine saved the cat.)