Of uncertain derivation; a fin (collectively) -- fins.
Englishman's Concordance
1) fin Part of Speech: noun masculine A Related Word by BDB/Strong’s Number: of uncertain derivation Same Word by TWOT Number: 1523
Brown-Driver-Briggs
סְנַמִּירnoun [masculine]fin (Late Hebrew id.; quadriliteral according to Sta§ 243; Fl in LevyNHWB iii. 725 a compare Aramaic סִמְמּוֺרִיןpoints, nails, and derive this from סַמֵּר verb nail, with infixed פ (LevyChWB ii. 507 b)); — Leviticus 11:9,10,12=Deuteronomy 14:9,10.
Englishman's Concordance (References)
Strong's Hebrew: 5579. senappir — 5 Occurrences
Leviticus 11:9 HEB:אֲשֶׁר־ לוֹ֩ סְנַפִּ֨יר וְקַשְׂקֶ֜שֶׂת בַּמַּ֗יִם NAS: all that have fins and scales, KJV: of all that [are] in the waters: whatsoever hath fins and scales INT: all after have fins and scales the water
Leviticus 11:10 HEB:אֵֽין־ ל֜וֹ סְנַפִּ֣יר וְקַשְׂקֶ֗שֶׂת בַּיַּמִּים֙ NAS: that does not have fins and scales KJV:And all that have not fins and scales INT: that have fins and scales the seas
Leviticus 11:12 HEB:אֵֽין־ ל֛וֹ סְנַפִּ֥יר וְקַשְׂקֶ֖שֶׂת בַּמָּ֑יִם NAS: does not have fins and scales KJV:Whatsoever hath no fins nor scales INT: does not have fins and scales the water
Deuteronomy 14:9 HEB:אֲשֶׁר־ ל֛וֹ סְנַפִּ֥יר וְקַשְׂקֶ֖שֶׂת תֹּאכֵֽלוּ׃ NAS: anything that has fins and scales KJV: of all that [are] in the waters: all that have fins and scales INT: anything after fins and scales may eat
Deuteronomy 14:10 HEB:אֵֽין־ ל֛וֹ סְנַפִּ֥יר וְקַשְׂקֶ֖שֶׂת לֹ֣א NAS: that does not have fins and scales KJV:And whatsoever hath not fins and scales INT: that have fins and scales shall not