1 nil, null, nothing, nought or naught, aught, cipher, Cricket duck, Colloq nix, US goose-egg, nada, niente, Slang Brit (sweet) Fanny Adams or F.A., bugger-all, US zilch:
Temperatures have remained below zero all day. The visiting team won three games, we won zero.
2 (rock) bottom, nadir:
On a scale of one to ten, she is a zero.
3 nobody, nothing, nonentity, Slang US nebbish, bupkis:
That fellow she married is a real zero.
4 zero in on. focus on, pinpoint, fix on, home in on, concentrate on, bring to bear on:
We zeroed in on the problem and then rapidly found the answer.