This is the 11976th most frequent Russian word.
защитил
"Defended" or "protected."
Here, 'защитил' refers to effectively presenting and defending one's academic work in front of an examination committee.
Студент защитил свой диплом на отлично.
The student successfully defended his thesis with distinction.
In this example, 'защитил' means to stand up for or safeguard one's reputation or dignity during a disagreement or conflict.
Он защитил свою честь в споре.
He defended his honor in a dispute.
Here, 'защитил' describes actively protecting or shielding a location or entity from an attack or encroachment.