Great question, not sure Just one more biscuit, only one more biscuit Just you believe in me, only you believe in me. (the former sounds odd) Just a minute! can suggest take a moment to stop, "Only a minute!" means something slightly different, along the lines it will take one minute, which is slightly different. Just one cornetto (is a famous advert), Only one cornetto.... sort of works Not sure if all the above helps but....

#Just The word “just” has several possible definitions: 1) Recently Be careful – I just washed the floor, and it’s still wet. (= I washed the floor a few minutes ago) He just finished a big project. (= he finished the project very recently) 2) Only I have just one brother. (= I have only one brother) I thought you were hungry, but you ate just half of your sandwich. (= you ate only half of your sandwich, and no more) #Only The word “only” can be replaced with “just” in most situations: Only two students came to class on the day before Christmas. = Just two students came to class on the day before Christmas. My kids only use the internet for schoolwork, not for playing games. = My kids just use the internet for schoolwork, not for playing games. In the expression “If only…” you can use “just” if you change the structure a little bit: If only I had studied harder. I would’ve passed the test. = If I had just studied harder, I would’ve passed the test. “Only” and “just” are interchangeable with definition 2 of “just,” but not with definition 1. Definition 2 – Same meaning We have just one daughter. = We have only one daughter. Definition 1 – Different meanings I just washed the floor (a few minutes ago) I only washed the floor (and I didn’t wash the table) However, it also depends on the context: “Did you clean the whole house?” “No, I just washed the floor” (= I only washed the floor). “Why is the floor wet?” “Because I just washed it” (= I recently washed it. In this case, you can’t use “only”)