quasi

Quasi is a prefix used in English to indicate likeness or partial inclusion, roughly meaning “almost” or “somewhat.” It comes from Latin quasi, meaning “almost” or “as if,” and is attached to nouns or adjectives to describe attributes that resemble something but are not fully realized.

In legal and administrative contexts, quasi- indicates that something resembles its formal counterpart but lacks full status, authority, or completeness. Examples include quasi-judicial bodies, which exercise some judicial-like powers, quasi-contracts, which arise by law to prevent unjust enrichment, and quasi-governmental agencies, which perform public functions without being fully sovereign entities.

In science and mathematics, quasi- appears in a variety of specialized terms. Quasi-experimental designs use observational data with some experimental features but lack random assignment. A quasicrystal exhibits long-range order without periodic repetition. Quasi-stellar objects, originally named for their star-like appearance, refer to quasars, extremely distant and energetic sources. In mathematics, quasi-orders, quasi-metrics, and quasi-norms describe relaxed or generalized structures that preserve core ideas while relaxing certain stringent requirements.

Across disciplines, quasi signals approximation, resemblance, or partial legitimacy, rather than full equivalence. The prefix remains productive for conveying partial analogy or transitional categories without redefining the base concept completely.