Liidetava

Liidetava is an Estonian term used as an adjective meaning “addable” or “capable of being added.” It is formed from the verb liitma (“to add” or “to join”) with the participial suffix -dav, and its inflected forms follow standard Estonian adjective patterns. The base form liidetav is used to describe something that can be added within a given context, while the genitive singular form liidetava appears in noun phrases, for example liidetava omaduse (the addable property).

In mathematics and formal logic, liidetav describes a property of a set or structure with respect to addition. A subset S is liidetav under addition if for any a and b in S, the sum a + b also lies in S. This condition is commonly referred to as closure under addition. For example, the set of natural numbers is liidetav under addition, since the sum of any two natural numbers is a natural number. The even numbers constitute a liidetav subset of the natural numbers, because the sum of two even numbers is even.

Beyond pure mathematics, the term can be used more generally to denote elements that can be combined or appended within a defined framework, such as components that can be concatenated or merged without violating system rules. The precise interpretation of liidetav depends on the operation defined in use (addition, concatenation, or other forms of combination).

See also: addition, closure property, Estonian language suffixes -dav/-atav.