What does base mean?
Base is a versatile English word whose core meaning is the lowest part of something — the foundation on which an object, structure, or idea rests. A statue sits on a base, a company operates from a base, and a recipe begins with a flavor base. Beyond the physical sense, base extends into many specialized fields: in chemistry, a base is a substance that neutralizes acids; in mathematics, it denotes the number of digits in a counting system such as base ten; in sports like baseball, bases mark the points a runner must touch. As an adjective, base can describe something morally low or contemptible, though this usage is now largely literary. Derived forms include 'based', 'baseline', and 'baseless'. Because it appears across architecture, science, military language, and daily conversation, base is an essential word for describing both literal foundations and figurative starting points.
The lowest part or foundation of something, or a central location from which activities are carried out.
"The climbers established a base camp at the foot of the mountain."
Commonly used in both concrete (physical) and abstract (conceptual) contexts.
To use a particular place as the location from which someone operates, or to form something on a particular source or premise.
"The film is based on a true story."
Usually appears in the passive construction 'be based on/in'.
Morally low, dishonorable, or without noble qualities.
"He was driven by base motives rather than genuine concern."
This sense is relatively formal or literary compared with the noun uses.
Pronounced /ˈbeɪsiːz/. Note that 'bases' is also the plural of 'basis'; context determines which singular is intended.
"The navy maintains several overseas bases."
Every pyramid, every argument, and every baseball run has one thing in common: they all need a base to stand on.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of base
Base comes from the Latin word 'basis', meaning a pedestal or foundation, which itself was borrowed from Greek 'basis' meaning 'a step or footing'. The word entered English via Old French 'base' around the late Middle Ages, initially referring to the bottom support of a column or structure. Over time its meaning broadened from physical foundations to abstract ones, giving rise to senses in chemistry, mathematics, and military terminology. Related words sharing the same root include 'basal', 'basement', 'debase', and 'abase'.
Related word forms
How base is actually used
As an adjective, 'base' can mean morally low or dishonorable (e.g., 'base motives'), a sense now somewhat formal or literary. In everyday use, 'base' as a noun dominates. The plural 'bases' is pronounced /ˈbeɪsiːz/ and should not be confused with the plural of 'basis', which is also 'bases' but pronounced /ˈbeɪsiːz/ — both share this pronunciation despite different singular forms.
Easily confused with base
'Bass' refers to low-frequency sound or a type of fish and is pronounced /beɪs/ in the musical sense but /bæs/ for the fish, while 'base' means a foundation or bottom support.