Body parts of which there are two form a special dual and end in –ayim and are of female gender.
Examples:
Singular | Plural | |
ear | אוזן | אוזניים |
ozen | oznayim | |
eye | עין | עניים |
ayin | enayim | |
tooth | שין | שיניים |
shen | shinayim | |
leg | רגל | רגליים |
regel | raglayim |
Singular | Plural | |
breast | שד | שדיים |
m shad | shadayim | |
lip | שפה | שפתיים |
safah | sfatayim | |
hip | מותן | מותניים |
m moten | motnayim | |
knee | ברך | ברכיים |
berech | berkayim |
Also certain objects form a dual-plural, but their gender is mostly male.
bycicle | אופניים |
ofanayim | |
hotplate (stove) | כיריים |
kirayim | |
crutches | קביים |
kabayim |
brackets | סוגריים |
sograyim | |
scissors | מספריים |
misparayim | |
pincers | מלקחיים |
melkachayim |
Why the word hotplates is a dual? Probably, because in pioneer times stoves had only two hotplates. Bye the way: The dual form exists similarly also in Arabic: eg. Bahrain (spoken bachrayn) means two seas, from al bachr, the sea.
Also, there are dual forms in notions of time.
noon | צהריים |
tzohorayim | |
two hours | שעתיים |
sha’atayim w | |
two days | יומיים |
yomayim |
two weeks | שבועיים |
shvu’ayjim | |
two months | חודשיים |
chodshayim | |
two years | שנתיים |
shnatayim w |