| photoperiodism |
the effect, as on growth or behaviors in plants or animals, caused by variations in the lengths of time they are exposed to light. |
| photophobia |
an abnormal fear of or painful sensitivity to light, sometimes resulting from eye ailments. |
| photopia |
vision during conditions of bright light or normal daylight. (Cf. scotopia.) |
| photoplay |
the written text of a play intended for presentation on film rather than on the stage; screenplay. |
| photoreceptor |
a cell on a sense organ or nerve, such as the eye or the optic nerve, that detects light, or the organ or nerve itself. |
| photosensitive |
sensitive to light or radiation. |
| photosphere |
the shining, visible surface of a star, esp. the sun. |
| Photostat |
trademark for a camera device used to make picturelike copies of printed matter. [3 definitions] |
| photostat |
to make a copy of (a document or the like) using a Photostat. |
| photosynthesis |
the process in plants by which sunlight, with the help of chlorophyll, is converted to chemical energy that is used to synthesize inorganic compounds into organic ones, esp. sugars. |
| photosynthesize |
to bring about or produce by the process of photosynthesis. |
| phototaxis |
the self-determined movement of an organism toward or away from light. |
| phototropic |
of, relating to, or influenced by phototropism. |
| phototropism |
the tendency of plants to turn or grow in a particular direction in response to light. |
| phototypesetting |
see "photocomposition." |
| photovoltaic |
pertaining to, producing, or utilizing voltage that has been generated using radiant energy. |
| photovoltaic cell |
a cell that produces electromotive force when it is exposed to radiation, esp. light; solar cell. |
| phr. |
abbreviation of "phrase." |
| phrasal |
pertaining to or consisting of one or more phrases. |
| phrase |
in grammar, a string of words that has meaning and grammatical order but does not have both a subject and a predicate. [11 definitions] |
| phraseology |
characteristic manner or style of verbal expression. [2 definitions] |