US Medical Term · anatomy
Spleen
Bazo
Where is the spleen?
MedlinePlus places the spleen above the stomach and under the ribs on the left side, and says it is about as big as a fist. The National Cancer Institute dictionary gives the same location in other words: the upper left side of the abdomen, under the ribs and above the stomach.
What does the spleen do?
According to MedlinePlus, the spleen contains white blood cells that fight germs, helps control the amount of blood in the body, and destroys old and damaged cells. The NCI dictionary adds that it filters the blood, makes lymphocytes (white blood cells), and stores blood cells. If the spleen is removed, MedlinePlus says other organs, such as the liver, will take over some of its work.
Terms built on the spleen
Splenomegaly (esplenomegalia) is a spleen that is larger than normal. Splenectomy (esplenectomía) is the name of the surgery to remove a damaged or diseased spleen; MedlinePlus en español states that after the spleen is removed, people are more likely to get infections. Its article on an enlarged spleen says to seek medical care right away if pain in the abdomen is severe or gets worse with a deep breath. Emergency signs need urgent care (call 911 in the U.S.).
What it means
The spleen is an organ above the stomach and under the ribs on the left side of the body, about as big as a fist. MedlinePlus describes it as part of the lymphatic system, which fights infection and keeps body fluids in balance; the National Cancer Institute (NCI) dictionary calls it part of the lymphatic and blood systems. The spleen filters the blood to help destroy microorganisms and get rid of old or damaged red blood cells, and it also makes lymphocytes (white blood cells) and stores blood cells. Certain diseases might cause the spleen to swell, and it can be damaged or ruptured in an injury. A person can live without a spleen, but the body loses some of its ability to fight infections.
Spleen in Spanish
- Spanish term
- Bazo
- Gender and article
- masculine: el bazo
- Pronunciation
- BAH-soh
Bazo is the word MedlinePlus en español uses for the organ, and it is masculine: el bazo. Two medical words MedlinePlus en español uses for a spleen problem and for spleen surgery do not contain bazo; they begin with esplen-. Esplenomegalia is a spleen that is larger than normal, and esplenectomía is the surgery to remove the spleen. The adjective follows the same pattern, as in arteria esplénica (splenic artery).
MedlinePlus en español also gives plain-language names. Among the alternative names for esplenomegalia it lists agrandamiento del bazo, bazo agrandado and hinchazón del bazo, and it titles its surgery article extirpación del bazo. Location words from the same pages are por arriba del estómago (above the stomach), debajo de las costillas (under the ribs) and la parte superior izquierda del abdomen (the upper left part of the abdomen). The system the spleen belongs to is el sistema linfático.
Phrases for an appointment
What a patient or a clinician might say, in English and Spanish:
| Who | English | Spanish |
|---|---|---|
| Clinician | I am going to press on the upper left side of your belly, just under your ribs. | Voy a presionarle la parte superior izquierda del abdomen, justo debajo de las costillas. |
| Patient | It hurts there, and I get full after eating very little. | Me duele ahí, y me lleno después de comer muy poco. |
| Clinician | Your spleen feels larger than normal. I am going to order an ultrasound of your abdomen. | Su bazo se siente más grande de lo normal. Voy a pedirle un ultrasonido del abdomen. |
| Patient | What does it mean to have an enlarged spleen? | ¿Qué significa tener el bazo agrandado? |
| Clinician | Have you ever had your spleen removed? | ¿Le han extirpado el bazo alguna vez? |
| Patient | Yes, they removed my spleen after a car accident. | Sí, me extirparon el bazo después de un accidente de auto. |
| Patient | Since I do not have a spleen, which vaccines do I need? | Como no tengo bazo, ¿qué vacunas necesito? |
| Clinician | If the pain in your belly becomes severe or gets worse when you take a deep breath, call 911 or go to the emergency room right away. | Si el dolor en el abdomen se vuelve intenso o empeora al respirar profundo, llame al 911 o vaya a la sala de emergencias de inmediato. |
In 9 languages
| Language | Term |
|---|---|
| English | Spleen |
| Spanish (Español) | Bazo |
| Chinese (中文) | 脾臟 |
| Korean (한국어) | 비장 |
| Vietnamese (Tiếng Việt) | Lá lách |
| Filipino (Tagalog) | Pali |
| Portuguese (Português) | Baço |
| Thai (ภาษาไทย) | ม้าม |
| Japanese (日本語) | 脾臓 |
Where you'll see it
Related terms
Your right to an interpreter in the United States
If English is not your primary language and you have difficulty communicating in English, you may need an interpreter or a translated document when you visit a doctor or dentist, go to the emergency room or pick up a prescription. The U.S. Department of Health and Human Services Office for Civil Rights states that two federal laws, Title VI of the Civil Rights Act of 1964 and Section 1557 of the Affordable Care Act, require programs that receive its funding to provide language access services free of charge.
You can ask when you make the appointment or at the front desk: "I need an interpreter, please." «Necesito un intérprete, por favor.»
More terms: Blood and immune system
All terms in this area: Blood and immune system — Sangre y sistema inmunitario
Sources
- Spleen Diseases — MedlinePlus, National Library of Medicine
- Enfermedades del bazo — MedlinePlus en español, Biblioteca Nacional de Medicina
- spleen — NCI Dictionary of Cancer Terms — National Cancer Institute (NCI), NIH
- Esplenomegalia (Enciclopedia médica) — MedlinePlus en español, Biblioteca Nacional de Medicina
- Extirpación del bazo (Enciclopedia médica) — MedlinePlus en español, Biblioteca Nacional de Medicina
- Limited English Proficiency (LEP): Your Right to Language Assistance Services — U.S. Department of Health and Human Services, Office for Civil Rights
This page is a language reference. It is not medical advice.
Last reviewed: October 7, 2026