The adjective הרה in classical Hebrew meant "pregnant" but was used as a noun to refer to a pregnant woman. The verb הרה meant to be or become pregnant. The Qumran Aramaic attestation of this verb (הרי) is probably a Hebraism (Cook, Dictionary of Qumran Aramaic, 65). It's interesting that the noun got used in modern Israeli Hebrew to refer to parents in general. The historical origins help to explain the feminine grammatical gender. Here's a wiki://en.wiktionary.org/wiki/Category:Hebrew_feminine_nouns_with_plurals_ending_in_־ים
“What’s this word ‘horim’ ?!” I ask my Israeli friend, and she answers with this Hebrew phrase. “Oh, my mom and my dad are my parents”, I mumble back as I work on memorizing the word. This is not such a far-fetched scenario. It will remove a lot of angst if people imagine Duolingo sentences in the context of learning a language!