# semilattice

> English word · Noun

## Definitions
1. A partially ordered set that either has a join (a least upper bound) for any nonempty finite subset (a join-semilattice or upper semilattice) or has a meet (or greatest lower bound) for any nonempty finite subset (a meet-semilattice or lower semilattice). Equivalently, an underlying set which has a binary operation which is associative, commutative, and idempotent.

## Etymology
From semi- + lattice.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/semilattice