सांसद, संसद में मतदाताओं का प्रतिनिधि होता है। अनेक देशों में इस शब्द का प्रयोग विशेष रूप से निम्न सदन के सदस्यों के लिए किया जाता है। क्योंकि प्रायः उच्च सदन के लिए एक अलग उपाधि जैसे कि सीनेट एवं इसके सदस्यों के लिये सीनेटर का प्रयोग किया जाता है सांसद अपनी राजनीतिक पार्टी के सदस्यों के साथ मिलकर संसदीय दल का गठन करते हैं।

A member of parliament (MP) is the representative in parliament of the people who live in their electoral district. In many countries with bicameral parliaments, this term refers only to members of the lower house since upper house members often have a different title. The terms congressman/congresswoman or deputy are equivalent terms used in other jurisdictions. The term parliamentarian is also sometimes used for members of parliament, but this may also be used to refer to unelected government officials with specific roles in a parliament and other expert advisers on parliamentary procedure such as the Senate parliamentarian in the United States. The term is also used to the characteristic of performing the duties of a member of a legislature, for example: "The two party leaders often disagreed on issues, but both were excellent parliamentarians and cooperated to get many good things done."