accumulator (noun) collector: one who collects specimens
Sinonime: act for,
alternate, answer for,
back up, be in place of,
change, commute, cover for, deputize,
displace, do the work of, double for, fill in for, fill one's position, go as,
proxy,
relieve,
replace, serve in one's stead,
spell, stand for, stand in for, sub,
supersede,
supplant,
swap, swap places with,
switch, take another's place,
take over