A primitive root; to hop, i.e. (figuratively) skip over (or spare); by implication, to hesitate; also (literally) to limp, to dance -- halt, become lame, leap, pass over.
I. מָּסַח verb pass or spring over; —
Qal Perfect3masculine singular ׳פ Exodus 12:27, ׳וּפ consecutive V:23 (J); 1 singular וּפָסַחְתִּ֫י 12:13 (P), all with עַל, of ׳י passing over (sparing) houses of Israel; Infinitive absolute מָּסוֺחַ Isaiah 31:5 a passing over (SC. עַליְֿרוּשָׁלַםִ).
II. [מָּסַח] verb limp (Thes below I. ׳פ but dubious; Arabic is dislocate; according to Gerber73 II. ׳פ is denominative from מִּסֵּחַ [and this below I. ׳פ?]); —
Qal Participle plural הַסְּעַמִּים עַלשְֿׁתֵּי מֹּסְחִים 1 Kings 18:21 figurative (see [ סְעִמָּה]).
Niph`al Imperfect3masculine singular וַיִּמָּסֵחַ וַיִּמֹּל 2 Samuel 4:4 and he fell and was made limping (lame).
Pi`el Imperfect3masculine plural עַלהַֿמִּזְבֵּחַ וַיְפַסְּחוּ 1 Kings 18:26 they went limping (along by the altar), i.e. probably in their dance, see Kit PietschmPhön. 220 (Gr ויפסעו [ = וַיִּפְשְׂעוּ] stepped).