sexually transmitted disease; STD; venereal disease
Medical and everyday term for infections spread through sexual contact. 性感染症 (せいかんせんしょう) is a more modern clinical term, but 性病 remains common.
Condoms are effective for preventing STDs.
He got tested for sexually transmitted diseases.
He once contracted an STD when he was young.
Unprotected sex increases the risk of becoming infected with an STD.
I was worried, so I went to get tested for STDs.
Using condoms can help prevent STDs.