cleisto-, cleist-, clisto-, clist-, cli-, clei-

1. A condition in which the foramen ovale of the heart fails to close.
2. An opening in the oval foramen of the heart.
3. A reference to the patency (opening) of the foramen (small opening) ovale of the heart.

In the fetal heart, the foramen ovale allows blood to enter the left atrium from the right atrium.

Applied to certain small inconspicuous permanently closed flowers, adapted for self-fertilization, occurring in various plants (e.g. Oxalis Acetosella, different species of Viola, etc.) on the same individuals as the normal larger brightly-colored flowers, which in such cases are either cross-fertilized or barren.

An intensive fear of closed spaces or of being locked in or of being in enclosed places.

A plant with closed spherical ascocarp.

A term used of fish which have the air bladder disconnected from the gut.

A reference to plants in which self-pollination takes place within flowers that remain closed because of abnormally cold conditions.