Nidhi sits next to 4 phonetic neighbors — Nidi, Nidha, and Niti are the closest matches by sound. Most share Nidhi's Indian-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"receptacle of divine riches"
"sage, seer"
"trustworthy, faithful"
"horse, swift as a horse"
"White antelope, graceful"
"friend, companion on the path"
"of high character, virtuous"
"strength, power"
"of the Ganges, daughter of sage Jahnu"
"grace, favor"
"musical instrument (vina), sacred to Saraswati"
"beauty, ornament, adornment"
"that which guides, that which leads"
"work, activity, to cultivate"
"belonging to Sharva (Shiva)"
"graceful, charming"
Similar sound: These names share phonetic patterns with Nidhi — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Sanskrit origins, giving them the same cultural heritage as Nidhi.
Rhythm: Nidhi is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.