apogee
apex
Zenith
ORIGMIorigin
Probably ZENITH which basically means utmost.
It is a word that contains two letter tiles worth 10 points each + a combination of one letter tile worth 3 points + four letter tiles worth 1 point apiece mostly vowels. And, one of the letter tiles with the highest points land on a double letter score and the word on a triple word score on the board.
apex
origin.
apex, acme
nadir
Origin, source
ghy
Zenith
Apex:From Chambers:apex noun (apexes or apices) 1 the highest point or tip. 2 geom the highest point of a plane or solid figure relative to some line or plane. 3 a climax or pinnacle. See also apical.ETYMOLOGY: 17c: Latin, meaning 'peak'.
a word opposite in meaning
Words meaning the highest point: * peak * climax * pinnacle * top
Highest point, hill top, hill peak.
PEAK