sag

He begins to sag ; i. e. to decline in his health. Norf. and Suff.

Sag
·noun State of sinking or bending; sagging. II. Sag ·vt To cause to bend or give way; to <<Load>>. ...

Webster's Dictionary of the English Language
to sag
To sink in the middle when supported at both ends; as a long pole.--Worcester. Provincial in England...

Dictionary of American Words And Phrases by John Russell Bartlett.