sə̇ˈnektəˌtüd, -ə.ˌtyüd noun
( -s )
Etymology: Medieval Latin senectitudin-, senectitudo, irregular from Latin senectus old age (from sen-, senic-, senex old, old man) + Latin -tudin-, -tudo -tude — more at senior
: old age 1
the mental changes of senescence and senectitude — Science