flexion

Everyday

1. (science, medical) Flexion is bending a joint so that the angle between the bones gets smaller, like bending your elbow or knee. tree →
2. (grammar, rare) Flexion can mean changing the ending of a word to show its grammar (more often called inflection). tree →

In the lessons

In PE and science lessons on muscles and joints, flexion is the opposite of extension (straightening). The biceps causes flexion of the elbow. Physiotherapists measure flexion after an injury. Phrases: «knee flexion», «flexion and extension».

Examples

• Bending your elbow is flexion. tree →
• Flexion and extension work like a hinge. tree →
• After his injury, he could only manage a little knee flexion. tree →
• The biceps muscle causes flexion of the arm. tree →
• Stretches improve flexion of the hips. tree →
• The physio measured the flexion of her ankle. tree →

Note

UK also spells it «flection» in old books. Related verb: flex (to bend). Opposite: extension.