di‧vid‧er /dəˈvaɪdə, dɪˈvaɪdə $ -ər/ noun [countable]

1. something that divides something else into parts:
a room divider
alphabetical file dividers

2. American English a piece of land that separates traffic travelling in opposite directions on a main road Synonym : reservation British English:
Police saw his Mercedes speeding along the center divider.

3.
dividers [plural] an instrument used for measuring or marking lines or angles, consisting of two pointed pieces of metal joined together at the top

[TahlilGaran] Dictionary of Contemporary English ▲