1. first thing - Noun
2. first thing - Adverb
Early in the morning.
I'll meet you first thing at the station.
Straight away, very soon.
The basic idea of how to do something.
I would help you, but I don't know the first thing about gardening.
Used other than figuratively or idiomatically: see first, thing.
Source: en.wiktionary.orgThe first thing I look for in a woman is warmth-femininity. It's got nothing to do with a pretty face. Kirk Douglas
If you find yourself in a hole, the first thing to do is stop digging. Will Rogers
Ironically, the first thing that appealed to me about Islam was its pluralism. The fact that the Koran praises all the great prophets of the past. Karen Armstrong
Do not say the first thing that comes to your mind. Kenyan Proverb
If you eat a live toad first thing in the morning, nothing worse will happen all day long. American Proverb
The first thing one should own is a home; and it is the last thing one should sell; for a home is ones tomb this side of heaven. Moroccan Proverb