abscise

Everyday

1. (science) To abscise means for a plant to drop a leaf, flower or fruit by forming a special layer of cells where it joins the stem. tree →
2. (formal) To abscise also means to cut something off. tree →

In the lessons

In science lessons on plants and seasons, trees abscise their leaves in autumn: a layer of cells (the abscission layer) forms at the bottom of the leaf stalk, and the leaf falls. It is a rare, technical word; everyday English says «drop» or «shed». Phrases: «abscise leaves», «abscission layer».

Examples

• In autumn, oak and maple trees abscise their leaves. tree →
• The plant abscises flowers that were not pollinated. tree →
• A corky layer forms before the leaf is abscised. tree →
• Some trees abscise small fruits when it is too dry. tree →
• Scientists study how plants decide when to abscise their leaves. tree →
• Evergreen trees abscise old needles a few at a time. tree →

Note

Rare technical word. Say «ab-SIZE». Noun: abscission (ab-SIZH-un). Not to be confused with «abscess» (a painful swelling full of pus) or «scissors», though «-scis-» comes from the same Latin root meaning «cut».