epiphysis

noun

epiph·​y·​sis i-ˈpi-fə-səs 

plural epiphyses i-ˈpi-fə-ˌsēz 

1

: a part or process of a bone that ossifies separately and later becomes ankylosed to the main part of the bone

especially : an end of a long bone

2

: pineal gland

Examples of epiphysis in a Sentence

Recent Examples on the Web

Pre-adolescents and teenagers can develop capital femoral epiphysis, a growth disorder that allows the femur to slide out of position. — Mark Gurarie, Health, 5 Apr. 2025

Meanwhile, the epiphyses on the ischium and the ends of the femur and shin bone (tibia) were well-developed but hadn’t yet fused—in other words, DH7 wasn’t a very young child but was definitely still growing. — Kiona N. Smith, Ars Technica, 10 Apr. 2020

Vidyadhar Upasani, a pediatric orthopedist at Rady Children’s Hospital in San Diego, uses 3-D printing to help plan intricate bone procedures to treat, for example, slipped capital femoral epiphysis, the most common hip disorder in adolescents. — Erin Blakemore, Washington Post, 11 June 2018

Word History

Etymology

New Latin, from Greek, growth, from epiphyesthai to grow on, from epi- + phyesthai to grow, middle voice of phyein to bring forth — more at be

First Known Use

1634, in the meaning defined at sense 1

Rhymes for epiphysis

• apophysis
• diaphysis
• dionysus
• hemolysis
• hypophysis
• metaphysis
• abscissas
• narcissus
• symphysis
• adenohypophysis
• electrophoresis
• neurohypophysis

Medical Definition

epiphysis

noun

epiph·​y·​sis i-ˈpif-ə-səs 

plural epiphyses -ˌsēz 

1

: a part or process of a bone that ossifies separately and later becomes ankylosed to the main part of the bone

especially : the usually rounded end of the shaft of a long bone that is composed mainly of cancellous bone covered by a thin layer of compact bone compare diaphysis

2

: pineal gland