A cikin kalandar wata, watan tsalle wata ƙarin wata ne da aka ƙara wa kalanda domin a ci gaba da daidaita kalandar wata da shekarar rana. Kalanda ta wata ta dogara ne akan zagayowar wata, wanda yake kimanin kwanaki 29.5, don haka shekarar wata tana da tsawon kwanaki 354. Wannan ya fi guntu fiye da shekarar rana, wanda yake kimanin kwanaki 365.24.
Domin a ci gaba da daidaita kalandar wata da shekarar rana, ana ƙara wata a kalandar wata kusan duk bayan shekaru uku. Ana saka watan tsalle bayan wani takamaiman wata a kalandar wata, kuma ana sanya masa suna iri ɗaya da wannan watan, amma tare da ƙara masa suna "tsalle". Misali, ana kiran watan tsalle bayan wata na uku "tsalle wata na uku" ko "wata na uku tsakanin watanni". Ana kuma ƙirga watan tsalle a matsayin wata na yau da kullun, kuma duk bukukuwa da bukukuwa da ke faruwa a wannan watan ana yin su kamar yadda aka saba.
Bukatar watan tsalle a kalandar wata ta taso ne saboda zagayowar wata da zagayowar rana ba su dace daidai ba. Ƙara watan tsalle yana tabbatar da cewa kalandar wata ta kasance daidai da yanayi, da kuma kalandar rana.
Lokacin Saƙo: Maris-23-2023