Le Deutéronome 23:2 Commentaire : Rashi, Chizkuni, Ibn Ezra & Rashbam

פצוע דכא means, one whose stones have been bruised (פצוע) or crushed (דכא) (Sifrei Devarim 247:1).

לא יבא פצוע דכה בקהל ה, someone with crushed private parts must not marry a Jewish woman. Seeing that such a person cannot sire children there is no point in his marrying a Jewish girl who will thus be prevented from becoming a mother.

gonads [Hebrew: dakkah] testicles (the word has no cognate). Some grammarians have offered an etymology from the tissue of a testicle, that it is “crushed” [Hebrew: dakkah] — but this is far-fetched.

וכרות שפכה means, one whose membrum has a cut in it, so that it no longer forcibly ejects a continuous flow of sperm but it pours it forth slowly, and he thus cannot beget children (Sifrei Devarim 247:2; Yevamot 75b).