nsf

(banking) Initialism of nonsufficient funds: the alert generated by a bounced check or an ACH transaction failure due to not enough money being in the account.

(US) Initialism of National Science Foundation.

(Internet, acronymy component) Initialism of not safe for [context] or not suitable for [context]: labels online content as being not appropriate for, and not to be clicked or displayed in, the named context; for example, NSFW (work), NSFL (life or lunch), NSFM (minors).

(medicine) Initialism of Nephrogenic Systemic Fibrosis, a rare syndrome that involves fibrosis of the skin, joints, eyes, and internal organs.