Ordinary girl with Ray going round yard (8)
I believe the answer is:
everyday
'ordinary' is the definition.
(similar in meaning)
'girl with ray going round yard' is the wordplay.
'girl' becomes 'eve' ().
'with' means one lot of letters go next to another.
'going round' means one lot of letters goes inside another (some letters go around others).
'yard' becomes 'yd' (abbreviation).
'ray' going around 'yd' is 'ryday'.
'eve'+'ryday'='EVERYDAY'
(Other definitions for everyday that I've seen before include "Run-of-the-mill" , "Common or usual" , "Commonplace and ordinary" , "Quotidian" , "Ordinary, for regular use" .)