only

1 only /ˈoʊnli/ adjective
1 only
/ˈoʊnli/
adjective
Britannica Dictionary definition of ONLY
always used before a noun
: alone in a class or category : existing with no other or others of the same kind — usually used with the or a possessive (such as my, her, its, their, John's, etc.)
— see also only child, the one and only at 3one

one of the only

: one of very few : one in a small class or category

the only

— used to emphasize that a particular person or thing should be the one chosen — usually + for
2 only /ˈoʊnli/ adverb
2 only
/ˈoʊnli/
adverb
Britannica Dictionary definition of ONLY
1 
a  : no more than
b  : nothing other than — used to indicate that a single thing was done, is needed, is possible, etc.
c  — used for emphasis
— sometimes used in the phrase only just
2 
: excluding all others
: nobody or nothing except
3 
a  : in no time, place, or situation except the one specified
b  : for no other reason than
4 
: nothing more important or serious than
5 
— used to emphasize that something happened recently
6 
a  — used to say that something has or will have a particular and usually bad result
b  — used to indicate something bad or surprising that happens after something else — followed by to + verb

for your eyes only

— see 1eye

if only

— see 1if

in name only

— see 1name

not only

— used to say that both of two related statements are true

only have eyes for

— see 1eye

only too

: very or completely

second only to

— see 1second
3 only /ˈoʊnli/ conjunction
3 only
/ˈoʊnli/
conjunction
Britannica Dictionary definition of ONLY
informal
: but, however