Verb
neck up (third-person singular simple present necks up, present participle necking up, simple past and past participle necked up)
(firearms) to increase the size of a cartridge's chamber and calibre.
Football is a game played with arms, legs and shoulders but mostly from the neck up. Knute Rockne
I never practiced a fretless ever, because the strings eat the neck up. So I would only play it on gigs. Jaco Pastorius
If we should have to fight, we should be prepared to so so from the neck up instead of from the neck down. Jimmy Doolittle
I may be paralyzed from the waist down, but unlike Gray Davis, I'm not paralyzed from the neck up. Larry Flynt