There are various synonyms for the phrase "have sexual intercourse." Some of the commonly used synonyms include making love, having sex, hooking up, copulating, mating, and engaging in sexual activity. Other synonyms may include getting intimate, gettin' busy, getting laid, and bumping uglies. It's important to remember that different individuals may opt to use different terms for various reasons. Regardless of the term used, it is important to consider getting informed consent before engaging in any sexual activity with another individual. Proper communication and making sure that both parties are comfortable and consenting can make for a better and more enjoyable experience for everyone involved.