Nigh on an amount, number, or age means almost that amount, number, or age. I had to pay nigh on forty pounds for it. = nearly
near in time or place or relationship; "as the wedding day drew near"; "stood near the door"; "don't shoot until they come near"; "getting near to the true explanation"; "her mother is always near"; "The end draws nigh"; "the bullet didn't come close"; "don't get too close to the fire"
(of actions or states) slightly short of or not quite accomplished; `near' is sometimes used informally for `nearly' and `most' is sometimes used informally for `almost'; "the job is (just) about done"; "the baby was almost asleep when the alarm sounded"; "we're almost finished"; "the car all but ran her down"; "he nearly fainted"; "talked for nigh onto 2 hours"; "the recording is well-nigh perfect"; "virtually all the parties signed the contract"; "I was near exhausted by the run"; "most everyone agrees"