PS

*rḥm - to be compassionate (Kogan 2015: 386)

PArm
*rḥm - to love (Kogan 2015:386, HALOT 1981)
PES
*mḥr - to have compassion; to have pity (SED I 204)
Related with metathesis.

Akkadian
rêmu - to take pity, to have mercy (CAD R 263, AHw. 970)
Hebrew
rḥm - (qal, pi.) to love, to meet someone with love, to take pity on someone (HALOT 1216)
Hebrew
raḥămīm - a feeling of love, loving sensation, mercy (HALOT 1218)
Official Aramaic
rḥm - to love (DNWSI 1068)
Biblical Aramaic
raḥămīn - Erbarmen (HALAT 1218)
Mandaic
rhm - to love, to have pity (MD 426)
Maalula
raḥmṯa - Barmhertzigkeit (GNDM 76)
Arabic
rḥm - to have mercy, pity, compassion (BK 1 838, Lane 1055)
Sabaic
rḥm - to be merciful (SD 116)
Mehri
rəḥām - to be kind to so. (ML 321)
Mehri
rəḥmēt - rain (ML 321)
Only a few attestations in MTO, as opposed to the main term for the meaning “rain” məwsē. Similarly, in MTjŠ rəḥmēt is more rare than məwsē, while in SAE III and IX the word seems to be the main exponent for the meaning (see Kogan 2015:515-516).
Jibbali
raḥám - to be kind (JL 210)
Harsusi
reḥām - to pity (HL 103)