Who is Rabbi Elazar ben Shammua? TB Ketubot 40

 The Hebrew word for a female orphan is yetoma (יְתוֹמָה). To prove that Rabbi Elazar’s position is the same as his teacher Rabbi Akiva, the Gemara quotes the Mishnah on today’s daf TB Ketubot 40 and explains gives the word yetoma a novel interpretation.

“And from where do we know that Rabbi Elazar’s opinion corresponds to the opinion of his teacher? From the fact that the mishna teaches with regard to an orphan that Rabbi Elazar says: One who rapes her is obligated to pay the fine and one who seduces her is exempt from payment.

“The Gemara asks: An orphan? That is obvious, as she has no father and is not subject to the authority of anyone else. Clearly the seducer is exempt from payment because she was complicit. Rather, this is what the mishna is teaching us: That the legal status of a young woman who was betrothed and divorced, even if her father is alive, is like that of an orphan: Just as with regard to an orphan, payment of the fine is to her, so too, with regard to a young woman who was betrothed and divorced, payment of the fine is to her.” (Sefaria.org translation). Once a young woman is betrothed and is either widowed or divorced, she is no longer under her father’s jurisdiction and is just like an orphan who has no father. That’s why the fine goes to her now instead of her father.

After declaring that the halakha is according to Rabbi Elazar, Rav says “Rav would exclaim about Rabbi Elazar: He is the happiest of the Sages, as he held that the halakha was ruled in accordance with his opinion in many instances.” (Sefaria.org translation)

Who is this Rabbi Elazar? Rashi identifies him as Rabbi Elazar ben Shammua. Rabbi Akiva had five outstanding students Rabbi Meir, Rabbi Yehuda, Rabbi Yosi, Rabbi Shimon, and Rabbi Elazar ben Shammua. “Eleazar ben Shammua was a student of Rabbi Akiva,^[4] but was not ordained by him due to the Hadrianic persecution. After Akiva's death, however, R. Judah ben Baba ordained Eleazar, together with Rabbi Meir, Jose ben Halafta, Judah bar Illai, and Simon bar Yoḥai, at a secluded spot between Usha and Shefar'am. The ordainer was detected in the act and brutally slain, but the ordained escaped, and eventually became the custodians and disseminators of Jewish tradition.^[5]

“Mention is made of a controversy between Eleazar and Rabbi Meir at Ardiska.^[6] He also maintained halakhic discussions with R. Judah bar Illai and Rabbi Jose,^[7] and quite frequently with R. Shimon bar Yochai;^[8] but he never appeared with them at the sessions of the Sanhedrin at Usha. Hence it may be assumed that he did not return to the scene of his ordination. Wherever he settled, he presided over an academy to which many students were attracted,^[9] including Joseph or Issi ha-Babli^[10] and Judah ha-Nasi.^[11] Thus, while his name does not appear in rabbinic lore as often as the names of his colleagues at the ordination, Eleazar had a significant influence on the development of the Talmud. Rav styles him "the most excellent among the sages",^[12] and R. Johanan expresses unbounded admiration for his large-heartedness.^[13]” (https://en.wikipedia.org/wiki/Eleazar_ben_Shammua)