literally: 'to fill the gap in between the teeth, used as a metaphor to emphazise the smallness or the insignificance of something, that it is virtually of little use or value (so small that it cannot even fill one's gap in their teeth)

gap (spoken)

not enough to fill the teeth gap, it means the portion of food is really small

buttcrack [colloquial]

remote

noun; complex terrain in the mountains

the gap(s) in between the fingers

a spendthrift; a wasteful or extravagant spender

verb; go to everywhere, even places off the beaten path; to try to connect with different people or network

any female who have reached suitable age for marriage, but not yet married, and unlikely to attract anyone to be with her

something that is very little and not enough / a very small return or profit than expected

a cleavage [colloquial]

a crack or a leak; a loophole; a flaw

gap between the teeth

big crack in a rock

(slang) someone is willing to spend money on prostitutes only

nooks and crannies

secret place

nooks and crannies [colloquial]

gaps between one's toes

(phrasal verb) to try to get or achieve something by taking advantage of the grey area of the rules or law; to exploit the legal loopholes

the gap / crack between the door and its frame

to get away; to slip through one's fingers [colloquial]

groin; gap between thighs (spoken)