"Tetrasomic" Natural Recordings by Native Speakers
A rare or exceptional feature of a chromosome: in some organisms, chromosome pairs have four rather than the usual two copies of each gene.
A tetrarchy is a system of government in which four persons, called tetrarchs, share power and authority.
A non-standard word that seems to be a portmanteau of "tetra" (meaning relating to four) and "hexakairos" (depending on the stress, "kaa"- which refers to construction – hence likely related to the deployment of the Latin term "-skelion," meaning, a bed or table), there isn't a widely recognized word in history or modern English called "tetraskelion".
Writing or structure consisting of four stanzas of four lines (or quatrains) each, typically presenting a theme or a complete thought.
A tetrastyle is a portico or porch having four columns, typically used to adorn the entrance of a ancient Greek or Roman building, particularly temples, theatres, and other public buildings.
Tetrathecal refers to a type of overlap of four elements or parts, often used in reference to anatomy, chemistry, or other scientific fields.