The word(s) "defend" appears 15 time(s) in 15 verse(s) in Quran in Abdullah Yusuf Ali translation.

(11) "A Day when ye shall turn your backs and flee: No defender shall ye have from Allah: Any whom Allah leaves to stray, there is none to guide...

(12) And those who, when an oppressive wrong is inflicted on them, (are not cowed but) help and defend themselves.

(13) But indeed if any do help and defend themselves after a wrong (done) to them, against such there is no cause of blame.

(14) Or do they say: "We acting together can defend ourselves"?

(15) It is He Who got out the Unbelievers among the People of the Book from their homes at the first gathering (of the forces). Little did ye think that they would get out: And they thought that their fortresses would defend them from Allah! But the (Wrath of) Allah came to them from quarters from which they little expected (it), and cast terror into their hearts, so that they destroyed their dwellings by their own hands and the hands of the Believers, take warning, then, O ye with eyes (to see)!