For "fresh" (bright, clean), the opposite could be dark, dirty, or grubby.
For "fresh" (new), antonyms include old, or used.
For "fresh" (original), the opposites could be unoriginal, hackneyed, or trite.
For "fresh" (rested) the opposite could be tired, or fatigued.
For food, the opposite could be stale or spoiled. For the condition in which food is obtained, the opposite of freshcould be canned, or preserved.
The opposite of new is usually "old."
Some variations are outmoded, outdated, or archaic.
NEW
The opposite could be new, recent, modern, or young.
The opposite of stale (food, air) would be fresh. The opposite of stale (tired, cliche) would be new, or original.
The opposite of legacy (left over, inherited) would be current, present, or new.
old
New.
The opposite of a new thing is an old thing.
The opposite of new is usually "old." Some variations are outmoded, outdated, or archaic.
New or young is opposite to old.
The opposite could be new, recent, modern, or young.
NEW
The opposite of a full moon is a new moon.
Advanced could be the opposite of primitive.Current, modern, new, present...
opposite flow
The opposite could be new, recent, modern, or young.
A homophone for the opposite of old and had an understanding of is "new" and "knew."
new.