Discernible (adjective)

1. Able to be seen or noticed.
2. Capable of being distinguished.

Origin:

Late 16th century: from medieval latin discernibilis, from the verb discernere (see discern).

Examples:

1. The difference in the two paintings was barely discernible.
2. There was a discernible change in his attitude.
3. The progress was barely discernible.
4. The improvement in her health was discernible.
5. The slight change in the weather was barely discernible.