Unknown.[1] Given the vast phonological variation and lack of usage in texts, probably borrowed from substrate. Related to भेड्र (bheḍra, “ram”), perhaps via the regular mh ~ bh alternation.[2]
Perhaps derived from मे॒ष (meṣá, “ram, sheep”), which is of Indo-European origin. A form like meṣ-ṭra undergoing Prakritisation could explain this term, but the exact suffix here is unclear.
Per Kuiper, borrowed from Munda.[3] Kuiper suggests a relationship to Pali meṇḍ (“crookedness”, root) and similar New Indo-Aryan terms referring to curved horns of animals.[4] These he traces to Munda terms including Mundari (meṇḍā, “curved and pointed to the head (horns)”), Ho (mendā), Santali (meṛha, “twisted backwards (horns of a buffalo)”). The rest of Kuiper's discussion on the etymology of the term is too speculative to list here.
The "penis" sense may come from a collision and conflation with the etymologically unrelated मेढ्र (meḍhra, “penis (organ of urination)”); see there for more.
मेण्ढ • (meṇḍha) stem, m
| Masculine a-stem declension of मेण्ढ (meṇḍha) | |||
|---|---|---|---|
| Singular | Dual | Plural | |
| Nominative | मेण्ढः meṇḍhaḥ |
मेण्ढौ / मेण्ढा¹ meṇḍhau / meṇḍhā¹ |
मेण्ढाः / मेण्ढासः¹ meṇḍhāḥ / meṇḍhāsaḥ¹ |
| Vocative | मेण्ढ meṇḍha |
मेण्ढौ / मेण्ढा¹ meṇḍhau / meṇḍhā¹ |
मेण्ढाः / मेण्ढासः¹ meṇḍhāḥ / meṇḍhāsaḥ¹ |
| Accusative | मेण्ढम् meṇḍham |
मेण्ढौ / मेण्ढा¹ meṇḍhau / meṇḍhā¹ |
मेण्ढान् meṇḍhān |
| Instrumental | मेण्ढेन meṇḍhena |
मेण्ढाभ्याम् meṇḍhābhyām |
मेण्ढैः / मेण्ढेभिः¹ meṇḍhaiḥ / meṇḍhebhiḥ¹ |
| Dative | मेण्ढाय meṇḍhāya |
मेण्ढाभ्याम् meṇḍhābhyām |
मेण्ढेभ्यः meṇḍhebhyaḥ |
| Ablative | मेण्ढात् meṇḍhāt |
मेण्ढाभ्याम् meṇḍhābhyām |
मेण्ढेभ्यः meṇḍhebhyaḥ |
| Genitive | मेण्ढस्य meṇḍhasya |
मेण्ढयोः meṇḍhayoḥ |
मेण्ढानाम् meṇḍhānām |
| Locative | मेण्ढे meṇḍhe |
मेण्ढयोः meṇḍhayoḥ |
मेण्ढेषु meṇḍheṣu |
| Notes |
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