Phonetic transliteration of 'Mortimer'. The characters approximate Mor-ti-mer:
莫 (mò) for 'Mor',
蒂 (dì) for 'ti',
默 (mò) for 'mer'.
默 'silent' is a common closing syllable for English -mer endings (cf.
福尔摩斯 Holmes uses
摩, but
默 is preferred when the syllable is unstressed).