Sentence:  In September ' 76 Thomas Huxley , Darwin 's famous disciple , came from England to speak in a crowded auditorium at the formal opening of the University ; and although it was a school for men only , it afforded Henrietta an opportunity to attend its <WSD>public</WSD> lectures . 
Meaning of the word marked with <WSD> tags:  a speech that is open to the public