It is not to forget and to offer shukr (gratitude), avoiding kufr (disbelief, here: ingratitude).
The third meaning is the purification of the qalb (the heart) from sins. This is the true taqwa (God-consciousness). (Minhāj, 27)
There are three degrees of taqwa: avoiding shirk (associating partners with God), avoiding bidʿa (innovations in religion), and