PWS

*ṭhr - to be pure (Kogan 2015: 123)

Ugaritic
ṭhr - pure, sparkling (DUL 888)
Phoenician
ṭhr - pure (DNWSI 420)
Hebrew
ṭhr - to be clean (HALOT 369)
Arabic
ṭhr - to be clean, pure (Lane 1886)
Arabic
ṭāhir - clean, pure (Lane 1887)
Sabaic
ṭhr - in a state of ritual purity (SD 153)
Geez
ṭahara - to be pure (CDG 589)
Mehri
ṭəhēr - to be ritually clean (ML 408)
an Arabism
Jibbali
ṭɛhέr - to be ritually clean (JL 275)
borrowed from Arb.