1. Capable of happening, existing, or being true without contradicting proven facts, laws, or circumstances: Is it possible to move faster than the speed of light?
2. Capable of becoming or of being made to be so; potential: possible suspects in the case; a possible site for the new capital.
3. Capable of occurring or being done in accordance with something specified. Used with the superlative: You'll get the best possible care at this hospital.
4. Capable of happening but of uncertain likelihood: It is possible that you might feel some discomfort after the procedure.
5. Permissible: Is it possible to enter the gallery at this hour?
[Middle English, from Old French, from Latin possibilis, from posse, to be able; see poti- in the Appendix of Indo-European roots.]
Synonyms: possible, workable, practicable, feasible, viable
These adjectives mean capable of occurring or being done. Possible indicates that something may happen, exist, be true, or be realizable: "I made out a list of questions and possible answers" (Mary Roberts Rinehart).
Workable is used of something that can be put into effective operation: If the scheme is workable, how will you implement it? Something that is practicable is capable of being effected, done, or put into practice: "As soon as it was practicable, he would wind up his business" (George Eliot).
Feasible refers to what can be accomplished, brought about, or carried out: Making cars by hand is possible but not economically feasible. Viable implies having the capacity for continuing effectiveness or success: "How viable are the ancient legends as vehicles for modern literary themes?" (Richard Kain).
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.