the best or most favorable point, degree, amount, etc., as of temperature, light, and moisture for the growth or reproduction of an organism.

the greatest degree or best result obtained or obtainable under specific conditions.

most favorable or desirable; best

optimum conditions.

adjective

least , poorest , worst

adjective

a1 , ace , capital , -carat , choice , choicest , excellent , flawless , gilt-edge , greatest , highest , ideal , matchless , maximum , most advantageous , most favorable , optimal , peak , peerless , perfect , select , solid gold , superlative , world class , unsurpassed , best , height , supreme , zenith