invalidum

Invalidum is the neuter singular form of the Latin adjective invalidus, which means weak, feeble, sick, or infirm. In classical Latin, the adjective appears in the standard second-declension paradigm: invalidus (masculine), valida (feminine), invalidum (neuter). The root of the word is from in- “not” plus valere “to be strong,” reflecting a sense of lack of strength or health.

Usage and semantics

In Latin texts, invalidus is used to describe physical or health-related weakness and can apply to people or things in a figurative sense. The masculine form is often found with nouns such as homo or vir to denote a person who is ill or infirm (for example, homo invalidus, “an invalid person”). The neuter form invalidum generally behaves as a descriptive adjective, and in some late or colloquial contexts may appear in a substantive sense, though such usage is less common and not standard for classical Latin.

Relationship to English

The Latin forms invalidus and invalidum are related to the English noun invalid, which originated from the same Latin family and, in modern English, refers to a disabled person or a person who is ill. However, invalidum itself is a grammatical form of a Latin adjective and is not used as an independent lexical item in English.

Modern significance

Today, invalidum is primarily of interest in the study of Latin grammar, morphology, and historical philology. It serves as an example of how adjectives agree with gender, number, and case in Latin, and how neuter singular forms can function within noun phrases or as stand-ins in certain textual contexts. References for further details include standard Latin grammars and dictionaries such as Lewis and Short.