Definition of sub-base in English:

sub-base

Pronunciation /ˈsʌbˌbeɪs/

noun

  • 1Architecture
    The lowest part of a horizontally divided base.

  • 2A base placed under the bottom of a machine or other apparatus to raise it; a base placed under another base.

  • 3A secondary station or base.

  • 4A layer underneath the base layer of a road, pavement, or the like; specifically one immediately above the subgrade.

Origin

Early 17th century. From sub- + base.