Synapsid

Synapsids (Greek, `fused arch`), synonymous with theropsids (Greek, `beast-face`), are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes. They are easily separated from other amniotes by having a temporal fenestra, an opening low in the skull roof behind each eye, leaving a ...
Found on http://en.wikipedia.org/wiki/Synapsid

Synapsid

(pronounced sin-AP-sid) Synapsids are a group of animals distinguished by having a skull with an extra low opening behind the eyes; this opening gave these animals stronger jaw muscles and jaws (the jaw muscles were anchored to the skull opening). Synapsids include the mammals , and extinct animals such as Dimetrodon . The pelycosaurs were early sy...
Found on http://www.enchantedlearning.com/subjects/dinosaurs/glossary/

synapsid

synapsid reptile noun extinct reptile having a single pair of lateral temporal openings in the skull
Found on https://www.encyclo.co.uk/local/20974

synapsid

n. A vertebrate distinguished by a skull with one pair of openings in the sidebehind the eyes, e.g., mammals and their close relatives.
Found on http://www.ucmp.berkeley.edu/glossary/glossary_7.html

synapsid

n. A vertebrate distinguished by a skull with one pair of openings in the sidebehind the eyes, e.g., mammals and their close relatives.
Found on http://www.ucmp.berkeley.edu/glossary/gloss7metazoa.html

synapsid

[n] - extinct reptile having a single pair of lateral temporal openings in the skull
Found on http://www.webdictionary.co.uk/definition.php?query=synapsid
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