If UNIFORM is coded as MROFINU, then ORPHAN is coded as

In letter-based coding-decoding, when a code word is formed by simply reversing the order of the letters of the given word, the SAME reverse-the-whole-word rule must be applied to encode or decode any other word under that scheme.

1. Write UNIFORM letter by letter: U-N-I-F-O-R-M (7 letters).

2. Reverse this order: it gives M-R-O-F-I-N-U, i.e. MROFINU -- exactly the coded form given in the question, confirming the rule is a full reversal.

3. Apply the same rule to ORPHAN: written letter by letter it is O-R-P-H-A-N (6 letters).

4. Reverse this order: it gives N-A-H-P-R-O, i.e. NAHPRO.

Reading NAHPRO backward letter by letter (O-R-P-H-A-N) reproduces ORPHAN exactly, confirming the reversal is correct and consistent with the UNIFORM to MROFINU pattern.