Worldly queen joining others in competition (11)
I believe the answer is:
terrestrial
'worldly' is the definition.
(similar in meaning)
'queen joining others in competition' is the wordplay.
'queen' becomes 'ER' (short for Elizabeth Regina ie Queen Elizabeth).
'joining' means one lot of letters go next to another.
'others' becomes 'rest' (eg the rest of a group).
'in' means one lot of letters goes inside another.
'competition' becomes 'trial' (I've seen this before).
'er'+'rest'='errest'
'errest' going inside 'trial' is 'TERRESTRIAL'.
(Other definitions for terrestrial that I've seen before include "Land-based" , "Relating to the earth" , "Not aquatic, arboreal, or aerial" , "Relating to dry land" , "Living on the ground" .)